XML 104 R45.htm IDEA: XBRL DOCUMENT v3.3.1.900
Benefit Plans (Tables)
 12 Months Ended
Dec. 31, 2015
Health Care Trend Rates
Health Care Trend Rates
 
2015
 
2014
Initial
 
6.25
%
 
6.50
%
Ultimate
 
5.00
%
 
5.00
%
Year Ultimate Reached
 
2020

 
2020
Effect of a 1% Change in Assumed Health Care Cost Trend Rates for the OPEB Health Care Plans
 
 
AEP
 
APCo
 
I&M
 
OPCo
 
PSO
 
SWEPCo
 
 
(in millions)
Effect on Total Service and Interest Cost Components of Net Periodic Postretirement Health Care Benefit Cost:
 
 
 
 
 
 
 
 
 
 
 
 
1% Increase
 
$
3.7

 
$
0.8

 
$
0.3

 
$
0.3

 
$
0.1

 
$
0.2

1% Decrease
 
(3.0
)
 
(0.6
)
 
(0.3
)
 
(0.2
)
 
(0.1
)
 
(0.1
)
 
 
 
 
 
 
 
 
 
 
 
 
 
Effect on the Health Care Component of the Accumulated Postretirement Benefit Obligation:
 
 
 
 
 
 
 
 
 
 
 
 
1% Increase
 
$
70.5

 
$
15.2

 
$
6.8

 
$
6.9

 
$
3.2

 
$
3.5

1% Decrease
 
(57.4
)
 
(12.3
)
 
(5.6
)
 
(5.7
)
 
(2.6
)
 
(2.9
)
Reconciliation of Changes in Benefit Obligations and Fair Value of Assets
AEP
 
Pension Plans
 
Other Postretirement
Benefit Plans
 
 
2015
 
2014
 
2015
 
2014
Change in Benefit Obligation
 
(in millions)
Benefit Obligation as of January 1,
 
$
5,224.9

 
$
4,841.7

 
$
1,439.0

 
$
1,455.5

Service Cost
 
93.5

 
71.9

 
12.2

 
14.2

Interest Cost
 
205.3

 
221.0

 
56.8

 
67.2

Actuarial (Gain) Loss
 
(200.6
)
 
387.0

 
37.2

 
(14.4
)
Benefit Payments
 
(330.2
)
 
(296.7
)
 
(128.7
)
 
(133.7
)
Participant Contributions
 
—

 
—

 
33.3

 
41.9

Medicare Subsidy
 
—

 
—

 
0.8

 
8.3

Benefit Obligation as of December 31,
 
$
4,992.9

 
$
5,224.9

 
$
1,450.6

 
$
1,439.0

 
 
 
 
 
 
 
 
 
Change in Fair Value of Plan Assets
 
 
 
 
 
 
 
 
Fair Value of Plan Assets as of January 1,
 
$
4,967.5

 
$
4,711.2

 
$
1,693.9

 
$
1,698.7

Actual Gain (Loss) on Plan Assets
 
32.4

 
474.2

 
(34.0
)
 
82.7

Company Contributions
 
97.9

 
78.8

 
12.9

 
4.3

Participant Contributions
 
—

 
—

 
33.3

 
41.9

Benefit Payments
 
(330.2
)
 
(296.7
)
 
(128.7
)
 
(133.7
)
Fair Value of Plan Assets as of December 31,
 
$
4,767.6

 
$
4,967.5

 
$
1,577.4

 
$
1,693.9

 
 
 
 
 
 
 
 
 
Funded (Underfunded) Status as of December 31,
 
$
(225.3
)
 
$
(257.4
)
 
$
126.8

 
$
254.9
Benefit Amounts Recognized on the Balance Sheets
 
 
Pension Plans
 
Other Postretirement
Benefit Plans
 
 
December 31,
AEP
 
2015
 
2014
 
2015
 
2014
 
 
(in millions)
Deferred Charges and Other Noncurrent Assets – Prepaid Benefit Costs
 
$
—

 
$
—

 
$
185.8

 
$
336.7

Other Current Liabilities – Accrued Short-term Benefit Liability
 
(6.3
)
 
(6.2
)
 
(3.3
)
 
(3.6
)
Employee Benefits and Pension Obligations – Accrued Long-term Benefit Liability
 
(219.0
)
 
(251.2
)
 
(55.7
)
 
(78.2
)
Funded (Underfunded) Status
 
$
(225.3
)
 
$
(257.4
)
 
$
126.8

 
$
254.9
Amounts Included in AOCI and Regulatory Assets
AEP
 
Pension Plans
 
Other Postretirement
Benefit Plans
 
 
December 31,
 
 
2015
 
2014
 
2015
 
2014
Components
 
(in millions)
Net Actuarial Loss
 
$
1,546.1

 
$
1,611.4

 
$
577.4

 
$
419.9

Prior Service Cost (Credit)
 
3.3

 
5.5

 
(554.4
)
 
(623.5
)
 
 
 
 
 
 
 
 
 
Recorded as
 
 
 
 
 
 
 
 
Regulatory Assets
 
$
1,385.2

 
$
1,418.3

 
$
15.1

 
$
(148.5
)
Deferred Income Taxes
 
57.5

 
69.5

 
2.8

 
(19.3
)
Net of Tax AOCI
 
106.7

 
129.1

 
5.1

 
(35.8
)
Components of Change in Amounts Included in AOCI and Regulatory Assets
AEP
 
Pension Plans
 
Other Postretirement
Benefit Plans
 
 
2015
 
2014
 
2015
 
2014
Components
 
(in millions)
Actuarial Loss During the Year
 
$
41.8

 
$
174.4

 
$
176.3

 
$
14.0

Amortization of Actuarial Loss
 
(107.1
)
 
(124.0
)
 
(18.8
)
 
(22.1
)
Amortization of Prior Service Credit (Cost)
 
(2.2
)
 
(2.5
)
 
69.1

 
69.0

Change for the Year Ended December 31,
 
$
(67.5
)
 
$
47.9

 
$
226.6

 
$
60.9
Accumulated Benefit Obligation
Accumulated Benefit Obligation
 
AEP
 
APCo
 
I&M
 
OPCo
 
PSO
 
SWEPCo
 
 
(in millions)
Qualified Pension Plan
 
$
4,757.1

 
$
641.4

 
$
571.3

 
$
484.1

 
$
252.0

 
$
267.7

Nonqualified Pension Plans
 
75.6

 
0.5

 
0.4

 
0.1

 
2.4

 
1.6

Total as of December 31, 2015
 
$
4,832.7

 
$
641.9

 
$
571.7

 
$
484.2

 
$
254.4

 
$
269.3

 
 
 
 
 
 
 
 
 
 
 
 
 
Accumulated Benefit Obligation
 
AEP
 
APCo
 
I&M
 
OPCo
 
PSO
 
SWEPCo
 
 
(in millions)
Qualified Pension Plan
 
$
4,982.0

 
$
688.6

 
$
598.2

 
$
512.4

 
$
270.0

 
$
281.2

Nonqualified Pension Plans
 
76.0

 
0.5

 
0.5

 
0.1

 
2.8

 
1.8

Total as of December 31, 2014
 
$
5,058.0

 
$
689.1

 
$
598.7

 
$
512.5

 
$
272.8

 
$
283.0
Underfunded Accumulated Benefit Obligation
 
AEP
 
APCo
 
I&M
 
OPCo
 
PSO
 
SWEPCo
 
(in millions)
Projected Benefit Obligation
$
4,992.9

 
$
653.4

 
$
591.5

 
$
497.5

 
$
2.6

 
$
1.7

 
 
 
 
 
 
 
 
 
 
 
 
Accumulated Benefit Obligation
$
4,832.7

 
$
641.9

 
$
571.7

 
$
484.2

 
$
2.4

 
$
1.6

Fair Value of Plan Assets
4,767.6

 
603.2

 
570.0

 
472.1

 
—

 
—

Underfunded Accumulated Benefit Obligation as of December 31, 2015
$
(65.1
)
 
$
(38.7
)
 
$
(1.7
)
 
$
(12.1
)
 
$
(2.4
)
 
$
(1.6
)
 
 
 
 
 
 
 
 
 
 
 
 
 
AEP
 
APCo
 
I&M
 
OPCo
 
PSO
 
SWEPCo
 
(in millions)
Projected Benefit Obligation
$
5,224.9

 
$
702.8

 
$
617.9

 
$
526.3

 
$
2.8

 
$
1.8

 
 
 
 
 
 
 
 
 
 
 
 
Accumulated Benefit Obligation
$
5,058.0

 
$
689.1

 
$
598.7

 
$
512.5

 
$
2.8

 
$
1.8

Fair Value of Plan Assets
4,967.5

 
642.3

 
591.7

 
498.5

 
—

 
—

Underfunded Accumulated Benefit Obligation as of December 31, 2014
$
(90.5
)
 
$
(46.8
)
 
$
(7.0
)
 
$
(14.0
)
 
$
(2.8
)
 
$
(1.8
)
Estimated Contributions and Payments to the Pension and OPEB Plans
Company
 
Pension Plans
 
Other Postretirement
Benefit Plans
 
 
(in millions)
AEP
 
$
95.6

 
$
6.0

APCo
 
10.7

 
2.6

I&M
 
13.1

 
—

OPCo
 
7.5

 
—

PSO
 
5.7

 
—

SWEPCo
 
6.9

 
—
Estimated Payments Expected to be Made by the Pension and OPEB Plans
Pension Plans
 
AEP
 
APCo
 
I&M
 
OPCo
 
PSO
 
SWEPCo
 
 
(in millions)
2016
 
$
324.0

 
$
42.8

 
$
33.9

 
$
36.4

 
$
19.3

 
$
18.6

2017
 
335.5

 
43.2

 
35.6

 
36.0

 
20.2

 
20.2

2018
 
339.3

 
44.2

 
36.0

 
35.8

 
20.1

 
21.1

2019
 
348.7

 
44.6

 
38.6

 
36.1

 
20.9

 
21.8

2020
 
355.9

 
45.0

 
39.3

 
36.2

 
21.3

 
22.4

Years 2021 to 2025, in Total
 
1,844.3

 
232.3

 
213.1

 
174.3

 
109.1

 
120.2

 
Other Postretirement Benefit Plans:
Benefit Payments
 
AEP
 
APCo
 
I&M
 
OPCo
 
PSO
 
SWEPCo
 
 
(in millions)
2016
 
$
134.1

 
$
25.3

 
$
15.9

 
$
16.9

 
$
7.4

 
$
7.9

2017
 
136.7

 
25.4

 
16.2

 
17.1

 
7.6

 
8.1

2018
 
139.1

 
25.6

 
16.6

 
17.3

 
7.7

 
8.3

2019
 
140.3

 
25.3

 
16.8

 
17.3

 
7.9

 
8.4

2020
 
143.6

 
25.6

 
17.2

 
17.5

 
8.1

 
8.7

Years 2021 to 2025, in Total
 
749.7

 
127.9

 
90.4

 
87.6

 
42.7

 
47.6

Other Postretirement Benefit Plans:
Medicare Subsidy Receipts
 
AEP
 
APCo
 
I&M
 
OPCo
 
PSO
 
SWEPCo
 
 
(in millions)
2016
 
$
0.3

 
$
0.2

 
$
—

 
$
—

 
$
—

 
$
—

2017
 
0.3

 
0.2

 
—

 
—

 
—

 
—

2018
 
0.3

 
0.2

 
—

 
—

 
—

 
—

2019
 
0.3

 
0.2

 
—

 
—

 
—

 
—

2020
 
0.3

 
0.2

 
—

 
—

 
—

 
—

Years 2021 to 2025, in Total
 
1.8

 
1.1

 
—

 
—

 
—

 
—
Components of Net Periodic Benefit Cost
AEP
Pension Plans
 
Other Postretirement
Benefit Plans
 
Years Ended December 31,
 
2015
 
2014
 
2013
 
2015
 
2014
 
2013
 
(in millions)
Service Cost
$
93.5

 
$
71.9

 
$
69.2

 
$
12.2

 
$
14.2

 
$
22.9

Interest Cost
205.3

 
221.0

 
202.8

 
56.8

 
67.2

 
70.8

Expected Return on Plan Assets
(274.8
)
 
(261.6
)
 
(277.8
)
 
(111.0
)
 
(111.3
)
 
(106.6
)
Amortization of Prior Service Cost (Credit)
2.2

 
2.5

 
2.8

 
(69.1
)
 
(69.0
)
 
(69.0
)
Amortization of Net Actuarial Loss
107.1

 
124.0

 
183.1

 
18.8

 
22.1

 
64.7

Net Periodic Benefit Cost (Credit)
133.3

 
157.8

 
180.1

 
(92.3
)
 
(76.8
)
 
(17.2
)
Capitalized Portion
(48.4
)
 
(52.2
)
 
(56.4
)
 
33.5

 
25.3

 
5.4

Net Periodic Benefit Cost (Credit) Recognized in Expense
$
84.9

 
$
105.6

 
$
123.7

 
$
(58.8
)
 
$
(51.5
)
 
$
(11.8
)
Estimated Amounts to be Amortized to Net Periodic Benefit Costs
 
 
AEP
 
APCo
 
I&M
 
OPCo
 
PSO
 
SWEPCo
Pension Plans – Components
 
(in millions)
Net Actuarial Loss
 
$
82.9

 
$
10.7

 
$
9.7

 
$
8.2

 
$
4.4

 
$
4.7

Prior Service Cost
 
2.2

 
0.2

 
0.2

 
0.1

 
0.2

 
0.3

Total Estimated 2016 Amortization
 
$
85.1

 
$
10.9

 
$
9.9

 
$
8.3

 
$
4.6

 
$
5.0

 
 
 
 
 
 
 
 
 
 
 
 
 
Pension Plans –
Expected to be Recorded as
 
 
 
 
 
 
 
 
 
 
 
 
Regulatory Asset
 
$
73.8

 
$
10.9

 
$
9.3

 
$
8.3

 
$
4.6

 
$
5.0

Deferred Income Taxes
 
3.9

 
—

 
0.2

 
—

 
—

 
—

Net of Tax AOCI
 
7.4

 
—

 
0.4

 
—

 
—

 
—

Total
 
$
85.1

 
$
10.9

 
$
9.9

 
$
8.3

 
$
4.6

 
$
5.0

 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
AEP
 
APCo
 
I&M
 
OPCo
 
PSO
 
SWEPCo
Other Postretirement Benefit Plans –
Components
 
(in millions)
Net Actuarial Loss
 
$
29.8

 
$
5.2

 
$
3.5

 
$
3.6

 
$
1.7

 
$
1.8

Prior Service Credit
 
(69.0
)
 
(10.1
)
 
(9.4
)
 
(6.9
)
 
(4.3
)
 
(5.1
)
Total Estimated 2016 Amortization
 
$
(39.2
)
 
$
(4.9
)
 
$
(5.9
)
 
$
(3.3
)
 
$
(2.6
)
 
$
(3.3
)
 
 
 
 
 
 
 
 
 
 
 
 
 
Other Postretirement Benefit Plans –
Expected to be Recorded as
 
 
 
 
 
 
 
 
 
 
 
 
Regulatory Asset
 
$
(28.5
)
 
$
(2.6
)
 
$
(5.3
)
 
$
(3.3
)
 
$
(2.6
)
 
$
(2.1
)
Deferred Income Taxes
 
(3.7
)
 
(0.8
)
 
(0.2
)
 
—

 
—

 
(0.4
)
Net of Tax AOCI
 
(7.0
)
 
(1.5
)
 
(0.4
)
 
—

 
—

 
(0.8
)
Total
 
$
(39.2
)
 
$
(4.9
)
 
$
(5.9
)
 
$
(3.3
)
 
$
(2.6
)
 
$
(3.3
)
Cost for Matching Contributions to the Retirement Savings Plans
 
 
Year Ended December 31,
Company
 
2015
 
2014
 
2013
 
 
(in millions)
AEP
 
$
73.6

 
$
70.5

 
$
66.6

APCo
 
7.2

 
7.3

 
7.4

I&M
 
10.6

 
10.5

 
10.0

OPCo
 
5.4

 
5.2

 
6.5

PSO
 
4.2

 
4.0

 
3.8

SWEPCo
 
5.7

 
5.3

 
5.0
Appalachian Power Co [Member]  
Health Care Trend Rates
Health Care Trend Rates
 
2015
 
2014
Initial
 
6.25
%
 
6.50
%
Ultimate
 
5.00
%
 
5.00
%
Year Ultimate Reached
 
2020

 
2020
Effect of a 1% Change in Assumed Health Care Cost Trend Rates for the OPEB Health Care Plans
 
 
AEP
 
APCo
 
I&M
 
OPCo
 
PSO
 
SWEPCo
 
 
(in millions)
Effect on Total Service and Interest Cost Components of Net Periodic Postretirement Health Care Benefit Cost:
 
 
 
 
 
 
 
 
 
 
 
 
1% Increase
 
$
3.7

 
$
0.8

 
$
0.3

 
$
0.3

 
$
0.1

 
$
0.2

1% Decrease
 
(3.0
)
 
(0.6
)
 
(0.3
)
 
(0.2
)
 
(0.1
)
 
(0.1
)
 
 
 
 
 
 
 
 
 
 
 
 
 
Effect on the Health Care Component of the Accumulated Postretirement Benefit Obligation:
 
 
 
 
 
 
 
 
 
 
 
 
1% Increase
 
$
70.5

 
$
15.2

 
$
6.8

 
$
6.9

 
$
3.2

 
$
3.5

1% Decrease
 
(57.4
)
 
(12.3
)
 
(5.6
)
 
(5.7
)
 
(2.6
)
 
(2.9
)
Reconciliation of Changes in Benefit Obligations and Fair Value of Assets
APCo
 
Pension Plans
 
Other Postretirement
Benefit Plans
 
 
2015
 
2014
 
2015
 
2014
Change in Benefit Obligation
 
(in millions)
Benefit Obligation as of January 1,
 
$
702.8

 
$
663.2

 
$
267.1

 
$
279.9

Service Cost
 
8.7

 
7.0

 
1.1

 
1.4

Interest Cost
 
26.7

 
29.6

 
10.3

 
12.8

Actuarial (Gain) Loss
 
(41.4
)
 
41.7

 
2.5

 
(9.0
)
Benefit Payments
 
(43.4
)
 
(38.7
)
 
(24.7
)
 
(26.6
)
Participant Contributions
 
—

 
—

 
5.7

 
7.2

Medicare Subsidy
 
—

 
—

 
0.2

 
1.4

Benefit Obligation as of December 31,
 
$
653.4

 
$
702.8

 
$
262.2

 
$
267.1

 
 
 
 
 
 
 
 
 
Change in Fair Value of Plan Assets
 
 
 
 
 
 
 
 
Fair Value of Plan Assets as of January 1,
 
$
642.3

 
$
628.0

 
$
280.6

 
$
284.8

Actual Gain (Loss) on Plan Assets
 
(5.7
)
 
44.0

 
(7.7
)
 
11.8

Company Contributions
 
10.0

 
9.0

 
2.8

 
3.4

Participant Contributions
 
—

 
—

 
5.7

 
7.2

Benefit Payments
 
(43.4
)
 
(38.7
)
 
(24.7
)
 
(26.6
)
Fair Value of Plan Assets as of December 31,
 
$
603.2

 
$
642.3

 
$
256.7

 
$
280.6

 
 
 
 
 
 
 
 
 
Funded (Underfunded) Status as of December 31,
 
$
(50.2
)
 
$
(60.5
)
 
$
(5.5
)
 
$
13.5
Benefit Amounts Recognized on the Balance Sheets
 
 
Pension Plans
 
Other Postretirement
Benefit Plans
 
 
December 31,
APCo
 
2015
 
2014
 
2015
 
2014
 
 
(in millions)
Deferred Charges and Other Noncurrent Assets – Prepaid Benefit Costs
 
$
—

 
$
—

 
$
30.8

 
$
56.5

Other Current Liabilities – Accrued Short-term Benefit Liability
 
—

 
—

 
(2.6
)
 
(2.9
)
Employee Benefits and Pension Obligations – Accrued Long-term Benefit Liability
 
(50.2
)
 
(60.5
)
 
(33.7
)
 
(40.1
)
Funded (Underfunded) Status
 
$
(50.2
)
 
$
(60.5
)
 
$
(5.5
)
 
$
13.5
Amounts Included in AOCI and Regulatory Assets
APCo
 
Pension Plans
 
Other Postretirement
Benefit Plans
 
 
December 31,
 
 
2015
 
2014
 
2015
 
2014
Components
 
(in millions)
Net Actuarial Loss
 
$
220.8

 
$
235.0

 
$
86.9

 
$
65.8

Prior Service Cost (Credit)
 
0.3

 
0.5

 
(80.6
)
 
(90.6
)
 
 
 
 
 
 
 
 
 
Recorded as
 
 
 
 
 
 
 
 
Regulatory Assets
 
$
218.3

 
$
232.8

 
$
(0.7
)
 
$
(20.3
)
Deferred Income Taxes
 
1.0

 
0.9

 
2.4

 
(1.6
)
Net of Tax AOCI
 
1.8

 
1.8

 
4.6

 
(2.9
)
Components of Change in Amounts Included in AOCI and Regulatory Assets
APCo
 
Pension Plans
 
Other Postretirement
Benefit Plans
 
 
2015
 
2014
 
2015
 
2014
Components
 
(in millions)
Actuarial (Gain) Loss During the Year
 
$
(0.3
)
 
$
31.6

 
$
24.7

 
$
(2.3
)
Amortization of Actuarial Loss
 
(13.9
)
 
(16.6
)
 
(3.6
)
 
(4.6
)
Amortization of Prior Service Credit (Cost)
 
(0.2
)
 
(0.2
)
 
10.0

 
10.1

Change for the Year Ended December 31,
 
$
(14.4
)
 
$
14.8

 
$
31.1

 
$
3.2
Allocated Assets of Investments
 
 
Pension Plan
 
Other Postretirement
Benefit Plans
Company
 
2015
 
2014
 
2015
 
2014
APCo
 
12.7
%
 
12.9
%
 
16.3
%
 
16.6
%
I&M
 
12.0
%
 
11.9
%
 
12.0
%
 
11.9
%
OPCo
 
9.9
%
 
10.0
%
 
12.1
%
 
12.2
%
PSO
 
5.5
%
 
5.5
%
 
5.6
%
 
5.7
%
SWEPCo
 
5.9
%
 
5.8
%
 
6.2
%
 
6.3
%
Accumulated Benefit Obligation
Accumulated Benefit Obligation
 
AEP
 
APCo
 
I&M
 
OPCo
 
PSO
 
SWEPCo
 
 
(in millions)
Qualified Pension Plan
 
$
4,757.1

 
$
641.4

 
$
571.3

 
$
484.1

 
$
252.0

 
$
267.7

Nonqualified Pension Plans
 
75.6

 
0.5

 
0.4

 
0.1

 
2.4

 
1.6

Total as of December 31, 2015
 
$
4,832.7

 
$
641.9

 
$
571.7

 
$
484.2

 
$
254.4

 
$
269.3

 
 
 
 
 
 
 
 
 
 
 
 
 
Accumulated Benefit Obligation
 
AEP
 
APCo
 
I&M
 
OPCo
 
PSO
 
SWEPCo
 
 
(in millions)
Qualified Pension Plan
 
$
4,982.0

 
$
688.6

 
$
598.2

 
$
512.4

 
$
270.0

 
$
281.2

Nonqualified Pension Plans
 
76.0

 
0.5

 
0.5

 
0.1

 
2.8

 
1.8

Total as of December 31, 2014
 
$
5,058.0

 
$
689.1

 
$
598.7

 
$
512.5

 
$
272.8

 
$
283.0
Underfunded Accumulated Benefit Obligation
 
AEP
 
APCo
 
I&M
 
OPCo
 
PSO
 
SWEPCo
 
(in millions)
Projected Benefit Obligation
$
4,992.9

 
$
653.4

 
$
591.5

 
$
497.5

 
$
2.6

 
$
1.7

 
 
 
 
 
 
 
 
 
 
 
 
Accumulated Benefit Obligation
$
4,832.7

 
$
641.9

 
$
571.7

 
$
484.2

 
$
2.4

 
$
1.6

Fair Value of Plan Assets
4,767.6

 
603.2

 
570.0

 
472.1

 
—

 
—

Underfunded Accumulated Benefit Obligation as of December 31, 2015
$
(65.1
)
 
$
(38.7
)
 
$
(1.7
)
 
$
(12.1
)
 
$
(2.4
)
 
$
(1.6
)
 
 
 
 
 
 
 
 
 
 
 
 
 
AEP
 
APCo
 
I&M
 
OPCo
 
PSO
 
SWEPCo
 
(in millions)
Projected Benefit Obligation
$
5,224.9

 
$
702.8

 
$
617.9

 
$
526.3

 
$
2.8

 
$
1.8

 
 
 
 
 
 
 
 
 
 
 
 
Accumulated Benefit Obligation
$
5,058.0

 
$
689.1

 
$
598.7

 
$
512.5

 
$
2.8

 
$
1.8

Fair Value of Plan Assets
4,967.5

 
642.3

 
591.7

 
498.5

 
—

 
—

Underfunded Accumulated Benefit Obligation as of December 31, 2014
$
(90.5
)
 
$
(46.8
)
 
$
(7.0
)
 
$
(14.0
)
 
$
(2.8
)
 
$
(1.8
)
Estimated Contributions and Payments to the Pension and OPEB Plans
Company
 
Pension Plans
 
Other Postretirement
Benefit Plans
 
 
(in millions)
AEP
 
$
95.6

 
$
6.0

APCo
 
10.7

 
2.6

I&M
 
13.1

 
—

OPCo
 
7.5

 
—

PSO
 
5.7

 
—

SWEPCo
 
6.9

 
—
Estimated Payments Expected to be Made by the Pension and OPEB Plans
Pension Plans
 
AEP
 
APCo
 
I&M
 
OPCo
 
PSO
 
SWEPCo
 
 
(in millions)
2016
 
$
324.0

 
$
42.8

 
$
33.9

 
$
36.4

 
$
19.3

 
$
18.6

2017
 
335.5

 
43.2

 
35.6

 
36.0

 
20.2

 
20.2

2018
 
339.3

 
44.2

 
36.0

 
35.8

 
20.1

 
21.1

2019
 
348.7

 
44.6

 
38.6

 
36.1

 
20.9

 
21.8

2020
 
355.9

 
45.0

 
39.3

 
36.2

 
21.3

 
22.4

Years 2021 to 2025, in Total
 
1,844.3

 
232.3

 
213.1

 
174.3

 
109.1

 
120.2

 
Other Postretirement Benefit Plans:
Benefit Payments
 
AEP
 
APCo
 
I&M
 
OPCo
 
PSO
 
SWEPCo
 
 
(in millions)
2016
 
$
134.1

 
$
25.3

 
$
15.9

 
$
16.9

 
$
7.4

 
$
7.9

2017
 
136.7

 
25.4

 
16.2

 
17.1

 
7.6

 
8.1

2018
 
139.1

 
25.6

 
16.6

 
17.3

 
7.7

 
8.3

2019
 
140.3

 
25.3

 
16.8

 
17.3

 
7.9

 
8.4

2020
 
143.6

 
25.6

 
17.2

 
17.5

 
8.1

 
8.7

Years 2021 to 2025, in Total
 
749.7

 
127.9

 
90.4

 
87.6

 
42.7

 
47.6

Other Postretirement Benefit Plans:
Medicare Subsidy Receipts
 
AEP
 
APCo
 
I&M
 
OPCo
 
PSO
 
SWEPCo
 
 
(in millions)
2016
 
$
0.3

 
$
0.2

 
$
—

 
$
—

 
$
—

 
$
—

2017
 
0.3

 
0.2

 
—

 
—

 
—

 
—

2018
 
0.3

 
0.2

 
—

 
—

 
—

 
—

2019
 
0.3

 
0.2

 
—

 
—

 
—

 
—

2020
 
0.3

 
0.2

 
—

 
—

 
—

 
—

Years 2021 to 2025, in Total
 
1.8

 
1.1

 
—

 
—

 
—

 
—
Components of Net Periodic Benefit Cost
APCo
Pension Plans
 
Other Postretirement
Benefit Plans
 
Years Ended December 31,
 
2015
 
2014
 
2013
 
2015
 
2014
 
2013
 
(in millions)
Service Cost
$
8.7

 
$
7.0

 
$
6.2

 
$
1.1

 
$
1.4

 
$
2.6

Interest Cost
26.7

 
29.6

 
27.7

 
10.3

 
12.8

 
13.5

Expected Return on Plan Assets
(35.0
)
 
(33.9
)
 
(37.1
)
 
(18.1
)
 
(18.5
)
 
(18.1
)
Amortization of Prior Service Cost (Credit)
0.2

 
0.2

 
0.2

 
(10.0
)
 
(10.1
)
 
(10.1
)
Amortization of Net Actuarial Loss
13.9

 
16.6

 
25.0

 
3.6

 
4.6

 
12.2

Net Periodic Benefit Cost (Credit)
14.5

 
19.5

 
22.0

 
(13.1
)
 
(9.8
)
 
0.1

Capitalized Portion
(5.5
)
 
(6.8
)
 
(7.5
)
 
5.0

 
3.4

 
(0.1
)
Net Periodic Benefit Cost (Credit) Recognized in Expense
$
9.0

 
$
12.7

 
$
14.5

 
$
(8.1
)
 
$
(6.4
)
 
$
—
Estimated Amounts to be Amortized to Net Periodic Benefit Costs
 
 
AEP
 
APCo
 
I&M
 
OPCo
 
PSO
 
SWEPCo
Pension Plans – Components
 
(in millions)
Net Actuarial Loss
 
$
82.9

 
$
10.7

 
$
9.7

 
$
8.2

 
$
4.4

 
$
4.7

Prior Service Cost
 
2.2

 
0.2

 
0.2

 
0.1

 
0.2

 
0.3

Total Estimated 2016 Amortization
 
$
85.1

 
$
10.9

 
$
9.9

 
$
8.3

 
$
4.6

 
$
5.0

 
 
 
 
 
 
 
 
 
 
 
 
 
Pension Plans –
Expected to be Recorded as
 
 
 
 
 
 
 
 
 
 
 
 
Regulatory Asset
 
$
73.8

 
$
10.9

 
$
9.3

 
$
8.3

 
$
4.6

 
$
5.0

Deferred Income Taxes
 
3.9

 
—

 
0.2

 
—

 
—

 
—

Net of Tax AOCI
 
7.4

 
—

 
0.4

 
—

 
—

 
—

Total
 
$
85.1

 
$
10.9

 
$
9.9

 
$
8.3

 
$
4.6

 
$
5.0

 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
AEP
 
APCo
 
I&M
 
OPCo
 
PSO
 
SWEPCo
Other Postretirement Benefit Plans –
Components
 
(in millions)
Net Actuarial Loss
 
$
29.8

 
$
5.2

 
$
3.5

 
$
3.6

 
$
1.7

 
$
1.8

Prior Service Credit
 
(69.0
)
 
(10.1
)
 
(9.4
)
 
(6.9
)
 
(4.3
)
 
(5.1
)
Total Estimated 2016 Amortization
 
$
(39.2
)
 
$
(4.9
)
 
$
(5.9
)
 
$
(3.3
)
 
$
(2.6
)
 
$
(3.3
)
 
 
 
 
 
 
 
 
 
 
 
 
 
Other Postretirement Benefit Plans –
Expected to be Recorded as
 
 
 
 
 
 
 
 
 
 
 
 
Regulatory Asset
 
$
(28.5
)
 
$
(2.6
)
 
$
(5.3
)
 
$
(3.3
)
 
$
(2.6
)
 
$
(2.1
)
Deferred Income Taxes
 
(3.7
)
 
(0.8
)
 
(0.2
)
 
—

 
—

 
(0.4
)
Net of Tax AOCI
 
(7.0
)
 
(1.5
)
 
(0.4
)
 
—

 
—

 
(0.8
)
Total
 
$
(39.2
)
 
$
(4.9
)
 
$
(5.9
)
 
$
(3.3
)
 
$
(2.6
)
 
$
(3.3
)
Cost for Matching Contributions to the Retirement Savings Plans
 
 
Year Ended December 31,
Company
 
2015
 
2014
 
2013
 
 
(in millions)
AEP
 
$
73.6

 
$
70.5

 
$
66.6

APCo
 
7.2

 
7.3

 
7.4

I&M
 
10.6

 
10.5

 
10.0

OPCo
 
5.4

 
5.2

 
6.5

PSO
 
4.2

 
4.0

 
3.8

SWEPCo
 
5.7

 
5.3

 
5.0
Indiana Michigan Power Co [Member]  
Health Care Trend Rates
Health Care Trend Rates
 
2015
 
2014
Initial
 
6.25
%
 
6.50
%
Ultimate
 
5.00
%
 
5.00
%
Year Ultimate Reached
 
2020

 
2020
Effect of a 1% Change in Assumed Health Care Cost Trend Rates for the OPEB Health Care Plans
 
 
AEP
 
APCo
 
I&M
 
OPCo
 
PSO
 
SWEPCo
 
 
(in millions)
Effect on Total Service and Interest Cost Components of Net Periodic Postretirement Health Care Benefit Cost:
 
 
 
 
 
 
 
 
 
 
 
 
1% Increase
 
$
3.7

 
$
0.8

 
$
0.3

 
$
0.3

 
$
0.1

 
$
0.2

1% Decrease
 
(3.0
)
 
(0.6
)
 
(0.3
)
 
(0.2
)
 
(0.1
)
 
(0.1
)
 
 
 
 
 
 
 
 
 
 
 
 
 
Effect on the Health Care Component of the Accumulated Postretirement Benefit Obligation:
 
 
 
 
 
 
 
 
 
 
 
 
1% Increase
 
$
70.5

 
$
15.2

 
$
6.8

 
$
6.9

 
$
3.2

 
$
3.5

1% Decrease
 
(57.4
)
 
(12.3
)
 
(5.6
)
 
(5.7
)
 
(2.6
)
 
(2.9
)
Reconciliation of Changes in Benefit Obligations and Fair Value of Assets
I&M
 
Pension Plans
 
Other Postretirement
Benefit Plans
 
 
2015
 
2014
 
2015
 
2014
Change in Benefit Obligation
 
(in millions)
Benefit Obligation as of January 1,
 
$
617.9

 
$
574.7

 
$
161.7

 
$
166.5

Service Cost
 
12.9

 
10.0

 
1.6

 
1.9

Interest Cost
 
24.5

 
26.3

 
6.4

 
7.6

Actuarial (Gain) Loss
 
(28.4
)
 
38.5

 
7.7

 
(4.9
)
Benefit Payments
 
(35.4
)
 
(31.6
)
 
(15.2
)
 
(15.7
)
Participant Contributions
 
—

 
—

 
4.0

 
5.2

Medicare Subsidy
 
—

 
—

 
0.1

 
1.1

Benefit Obligation as of December 31,
 
$
591.5

 
$
617.9

 
$
166.3

 
$
161.7

 
 
 
 
 
 
 
 
 
Change in Fair Value of Plan Assets
 
 
 
 
 
 
 
 
Fair Value of Plan Assets as of January 1,
 
$
591.7

 
$
559.1

 
$
202.4

 
$
206.2

Actual Gain (Loss) on Plan Assets
 
(0.9
)
 
55.3

 
(2.3
)
 
6.6

Company Contributions
 
14.6

 
8.9

 
0.1

 
0.1

Participant Contributions
 
—

 
—

 
4.0

 
5.2

Benefit Payments
 
(35.4
)
 
(31.6
)
 
(15.2
)
 
(15.7
)
Fair Value of Plan Assets as of December 31,
 
$
570.0

 
$
591.7

 
$
189.0

 
$
202.4

 
 
 
 
 
 
 
 
 
Funded (Underfunded) Status as of December 31,
 
$
(21.5
)
 
$
(26.2
)
 
$
22.7

 
$
40.7
Benefit Amounts Recognized on the Balance Sheets
 
 
Pension Plans
 
Other Postretirement
Benefit Plans
 
 
December 31,
I&M
 
2015
 
2014
 
2015
 
2014
 
 
(in millions)
Deferred Charges and Other Noncurrent Assets – Prepaid Benefit Costs
 
$
—

 
$
—

 
$
22.7

 
$
40.7

Deferred Credits and Other Noncurrent Liabilities – Accrued Long-term Benefit Liability
 
(21.5
)
 
(26.2
)
 
—

 
—

Funded (Underfunded) Status
 
$
(21.5
)
 
$
(26.2
)
 
$
22.7

 
$
40.7
Amounts Included in AOCI and Regulatory Assets
I&M
 
Pension Plans
 
Other Postretirement
Benefit Plans
 
 
December 31,
 
 
2015
 
2014
 
2015
 
2014
Components
 
(in millions)
Net Actuarial Loss
 
$
130.0

 
$
137.9

 
$
77.1

 
$
54.4

Prior Service Cost (Credit)
 
0.3

 
0.5

 
(75.7
)
 
(85.1
)
 
 
 
 
 
 
 
 
 
Recorded as
 
 
 
 
 
 
 
 
Regulatory Assets
 
$
125.3

 
$
134.1

 
$
1.1

 
$
(26.3
)
Deferred Income Taxes
 
1.8

 
1.5

 
0.1

 
(1.5
)
Net of Tax AOCI
 
3.2

 
2.8

 
0.2

 
(2.9
)
Components of Change in Amounts Included in AOCI and Regulatory Assets
I&M
 
Pension Plans
 
Other Postretirement
Benefit Plans
 
 
2015
 
2014
 
2015
 
2014
Components
 
(in millions)
Actuarial Loss During the Year
 
$
4.7

 
$
14.2

 
$
24.7

 
$
1.9

Amortization of Actuarial Loss
 
(12.6
)
 
(14.6
)
 
(2.0
)
 
(2.4
)
Amortization of Prior Service Credit (Cost)
 
(0.2
)
 
(0.2
)
 
9.4

 
9.4

Change for the Year Ended December 31,
 
$
(8.1
)
 
$
(0.6
)
 
$
32.1

 
$
8.9
Allocated Assets of Investments
 
 
Pension Plan
 
Other Postretirement
Benefit Plans
Company
 
2015
 
2014
 
2015
 
2014
APCo
 
12.7
%
 
12.9
%
 
16.3
%
 
16.6
%
I&M
 
12.0
%
 
11.9
%
 
12.0
%
 
11.9
%
OPCo
 
9.9
%
 
10.0
%
 
12.1
%
 
12.2
%
PSO
 
5.5
%
 
5.5
%
 
5.6
%
 
5.7
%
SWEPCo
 
5.9
%
 
5.8
%
 
6.2
%
 
6.3
%
Accumulated Benefit Obligation
Accumulated Benefit Obligation
 
AEP
 
APCo
 
I&M
 
OPCo
 
PSO
 
SWEPCo
 
 
(in millions)
Qualified Pension Plan
 
$
4,757.1

 
$
641.4

 
$
571.3

 
$
484.1

 
$
252.0

 
$
267.7

Nonqualified Pension Plans
 
75.6

 
0.5

 
0.4

 
0.1

 
2.4

 
1.6

Total as of December 31, 2015
 
$
4,832.7

 
$
641.9

 
$
571.7

 
$
484.2

 
$
254.4

 
$
269.3

 
 
 
 
 
 
 
 
 
 
 
 
 
Accumulated Benefit Obligation
 
AEP
 
APCo
 
I&M
 
OPCo
 
PSO
 
SWEPCo
 
 
(in millions)
Qualified Pension Plan
 
$
4,982.0

 
$
688.6

 
$
598.2

 
$
512.4

 
$
270.0

 
$
281.2

Nonqualified Pension Plans
 
76.0

 
0.5

 
0.5

 
0.1

 
2.8

 
1.8

Total as of December 31, 2014
 
$
5,058.0

 
$
689.1

 
$
598.7

 
$
512.5

 
$
272.8

 
$
283.0
Underfunded Accumulated Benefit Obligation
 
AEP
 
APCo
 
I&M
 
OPCo
 
PSO
 
SWEPCo
 
(in millions)
Projected Benefit Obligation
$
4,992.9

 
$
653.4

 
$
591.5

 
$
497.5

 
$
2.6

 
$
1.7

 
 
 
 
 
 
 
 
 
 
 
 
Accumulated Benefit Obligation
$
4,832.7

 
$
641.9

 
$
571.7

 
$
484.2

 
$
2.4

 
$
1.6

Fair Value of Plan Assets
4,767.6

 
603.2

 
570.0

 
472.1

 
—

 
—

Underfunded Accumulated Benefit Obligation as of December 31, 2015
$
(65.1
)
 
$
(38.7
)
 
$
(1.7
)
 
$
(12.1
)
 
$
(2.4
)
 
$
(1.6
)
 
 
 
 
 
 
 
 
 
 
 
 
 
AEP
 
APCo
 
I&M
 
OPCo
 
PSO
 
SWEPCo
 
(in millions)
Projected Benefit Obligation
$
5,224.9

 
$
702.8

 
$
617.9

 
$
526.3

 
$
2.8

 
$
1.8

 
 
 
 
 
 
 
 
 
 
 
 
Accumulated Benefit Obligation
$
5,058.0

 
$
689.1

 
$
598.7

 
$
512.5

 
$
2.8

 
$
1.8

Fair Value of Plan Assets
4,967.5

 
642.3

 
591.7

 
498.5

 
—

 
—

Underfunded Accumulated Benefit Obligation as of December 31, 2014
$
(90.5
)
 
$
(46.8
)
 
$
(7.0
)
 
$
(14.0
)
 
$
(2.8
)
 
$
(1.8
)
Estimated Contributions and Payments to the Pension and OPEB Plans
Company
 
Pension Plans
 
Other Postretirement
Benefit Plans
 
 
(in millions)
AEP
 
$
95.6

 
$
6.0

APCo
 
10.7

 
2.6

I&M
 
13.1

 
—

OPCo
 
7.5

 
—

PSO
 
5.7

 
—

SWEPCo
 
6.9

 
—
Estimated Payments Expected to be Made by the Pension and OPEB Plans
Pension Plans
 
AEP
 
APCo
 
I&M
 
OPCo
 
PSO
 
SWEPCo
 
 
(in millions)
2016
 
$
324.0

 
$
42.8

 
$
33.9

 
$
36.4

 
$
19.3

 
$
18.6

2017
 
335.5

 
43.2

 
35.6

 
36.0

 
20.2

 
20.2

2018
 
339.3

 
44.2

 
36.0

 
35.8

 
20.1

 
21.1

2019
 
348.7

 
44.6

 
38.6

 
36.1

 
20.9

 
21.8

2020
 
355.9

 
45.0

 
39.3

 
36.2

 
21.3

 
22.4

Years 2021 to 2025, in Total
 
1,844.3

 
232.3

 
213.1

 
174.3

 
109.1

 
120.2

 
Other Postretirement Benefit Plans:
Benefit Payments
 
AEP
 
APCo
 
I&M
 
OPCo
 
PSO
 
SWEPCo
 
 
(in millions)
2016
 
$
134.1

 
$
25.3

 
$
15.9

 
$
16.9

 
$
7.4

 
$
7.9

2017
 
136.7

 
25.4

 
16.2

 
17.1

 
7.6

 
8.1

2018
 
139.1

 
25.6

 
16.6

 
17.3

 
7.7

 
8.3

2019
 
140.3

 
25.3

 
16.8

 
17.3

 
7.9

 
8.4

2020
 
143.6

 
25.6

 
17.2

 
17.5

 
8.1

 
8.7

Years 2021 to 2025, in Total
 
749.7

 
127.9

 
90.4

 
87.6

 
42.7

 
47.6

Other Postretirement Benefit Plans:
Medicare Subsidy Receipts
 
AEP
 
APCo
 
I&M
 
OPCo
 
PSO
 
SWEPCo
 
 
(in millions)
2016
 
$
0.3

 
$
0.2

 
$
—

 
$
—

 
$
—

 
$
—

2017
 
0.3

 
0.2

 
—

 
—

 
—

 
—

2018
 
0.3

 
0.2

 
—

 
—

 
—

 
—

2019
 
0.3

 
0.2

 
—

 
—

 
—

 
—

2020
 
0.3

 
0.2

 
—

 
—

 
—

 
—

Years 2021 to 2025, in Total
 
1.8

 
1.1

 
—

 
—

 
—

 
—
Components of Net Periodic Benefit Cost
I&M
Pension Plans
 
Other Postretirement
Benefit Plans
 
Years Ended December 31,
 
2015
 
2014
 
2013
 
2015
 
2014
 
2013
 
(in millions)
Service Cost
$
12.9

 
$
10.0

 
$
8.7

 
$
1.6

 
$
1.9

 
$
3.2

Interest Cost
24.5

 
26.3

 
24.1

 
6.4

 
7.6

 
8.2

Expected Return on Plan Assets
(32.6
)
 
(31.0
)
 
(32.8
)
 
(13.2
)
 
(13.4
)
 
(13.2
)
Amortization of Prior Service Cost (Credit)
0.2

 
0.2

 
0.2

 
(9.4
)
 
(9.4
)
 
(9.4
)
Amortization of Net Actuarial Loss
12.6

 
14.6

 
21.7

 
2.0

 
2.4

 
7.5

Net Periodic Benefit Cost (Credit)
17.6

 
20.1

 
21.9

 
(12.6
)
 
(10.9
)
 
(3.7
)
Capitalized Portion
(4.0
)
 
(4.6
)
 
(4.6
)
 
2.9

 
2.5

 
0.8

Net Periodic Benefit Cost (Credit) Recognized in Expense
$
13.6

 
$
15.5

 
$
17.3

 
$
(9.7
)
 
$
(8.4
)
 
$
(2.9
)
Estimated Amounts to be Amortized to Net Periodic Benefit Costs
 
 
AEP
 
APCo
 
I&M
 
OPCo
 
PSO
 
SWEPCo
Pension Plans – Components
 
(in millions)
Net Actuarial Loss
 
$
82.9

 
$
10.7

 
$
9.7

 
$
8.2

 
$
4.4

 
$
4.7

Prior Service Cost
 
2.2

 
0.2

 
0.2

 
0.1

 
0.2

 
0.3

Total Estimated 2016 Amortization
 
$
85.1

 
$
10.9

 
$
9.9

 
$
8.3

 
$
4.6

 
$
5.0

 
 
 
 
 
 
 
 
 
 
 
 
 
Pension Plans –
Expected to be Recorded as
 
 
 
 
 
 
 
 
 
 
 
 
Regulatory Asset
 
$
73.8

 
$
10.9

 
$
9.3

 
$
8.3

 
$
4.6

 
$
5.0

Deferred Income Taxes
 
3.9

 
—

 
0.2

 
—

 
—

 
—

Net of Tax AOCI
 
7.4

 
—

 
0.4

 
—

 
—

 
—

Total
 
$
85.1

 
$
10.9

 
$
9.9

 
$
8.3

 
$
4.6

 
$
5.0

 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
AEP
 
APCo
 
I&M
 
OPCo
 
PSO
 
SWEPCo
Other Postretirement Benefit Plans –
Components
 
(in millions)
Net Actuarial Loss
 
$
29.8

 
$
5.2

 
$
3.5

 
$
3.6

 
$
1.7

 
$
1.8

Prior Service Credit
 
(69.0
)
 
(10.1
)
 
(9.4
)
 
(6.9
)
 
(4.3
)
 
(5.1
)
Total Estimated 2016 Amortization
 
$
(39.2
)
 
$
(4.9
)
 
$
(5.9
)
 
$
(3.3
)
 
$
(2.6
)
 
$
(3.3
)
 
 
 
 
 
 
 
 
 
 
 
 
 
Other Postretirement Benefit Plans –
Expected to be Recorded as
 
 
 
 
 
 
 
 
 
 
 
 
Regulatory Asset
 
$
(28.5
)
 
$
(2.6
)
 
$
(5.3
)
 
$
(3.3
)
 
$
(2.6
)
 
$
(2.1
)
Deferred Income Taxes
 
(3.7
)
 
(0.8
)
 
(0.2
)
 
—

 
—

 
(0.4
)
Net of Tax AOCI
 
(7.0
)
 
(1.5
)
 
(0.4
)
 
—

 
—

 
(0.8
)
Total
 
$
(39.2
)
 
$
(4.9
)
 
$
(5.9
)
 
$
(3.3
)
 
$
(2.6
)
 
$
(3.3
)
Cost for Matching Contributions to the Retirement Savings Plans
 
 
Year Ended December 31,
Company
 
2015
 
2014
 
2013
 
 
(in millions)
AEP
 
$
73.6

 
$
70.5

 
$
66.6

APCo
 
7.2

 
7.3

 
7.4

I&M
 
10.6

 
10.5

 
10.0

OPCo
 
5.4

 
5.2

 
6.5

PSO
 
4.2

 
4.0

 
3.8

SWEPCo
 
5.7

 
5.3

 
5.0
Ohio Power Co [Member]  
Health Care Trend Rates
Health Care Trend Rates
 
2015
 
2014
Initial
 
6.25
%
 
6.50
%
Ultimate
 
5.00
%
 
5.00
%
Year Ultimate Reached
 
2020

 
2020
Effect of a 1% Change in Assumed Health Care Cost Trend Rates for the OPEB Health Care Plans
 
 
AEP
 
APCo
 
I&M
 
OPCo
 
PSO
 
SWEPCo
 
 
(in millions)
Effect on Total Service and Interest Cost Components of Net Periodic Postretirement Health Care Benefit Cost:
 
 
 
 
 
 
 
 
 
 
 
 
1% Increase
 
$
3.7

 
$
0.8

 
$
0.3

 
$
0.3

 
$
0.1

 
$
0.2

1% Decrease
 
(3.0
)
 
(0.6
)
 
(0.3
)
 
(0.2
)
 
(0.1
)
 
(0.1
)
 
 
 
 
 
 
 
 
 
 
 
 
 
Effect on the Health Care Component of the Accumulated Postretirement Benefit Obligation:
 
 
 
 
 
 
 
 
 
 
 
 
1% Increase
 
$
70.5

 
$
15.2

 
$
6.8

 
$
6.9

 
$
3.2

 
$
3.5

1% Decrease
 
(57.4
)
 
(12.3
)
 
(5.6
)
 
(5.7
)
 
(2.6
)
 
(2.9
)
Reconciliation of Changes in Benefit Obligations and Fair Value of Assets
OPCo
 
Pension Plans
 
Other Postretirement
Benefit Plans
 
 
2015
 
2014
 
2015
 
2014
Change in Benefit Obligation
 
(in millions)
Benefit Obligation as of January 1,
 
$
526.3

 
$
523.6

 
$
164.7

 
$
171.2

Service Cost
 
6.7

 
5.2

 
0.9

 
1.0

Interest Cost
 
20.3

 
22.1

 
6.4

 
7.6

Actuarial (Gain) Loss
 
(19.5
)
 
6.8

 
8.7

 
(4.3
)
Benefit Payments
 
(36.3
)
 
(31.4
)
 
(16.3
)
 
(17.4
)
Participant Contributions
 
—

 
—

 
4.3

 
5.6

Medicare Subsidy
 
—

 
—

 
(0.1
)
 
1.0

Benefit Obligation as of December 31,
 
$
497.5

 
$
526.3

 
$
168.6

 
$
164.7

 
 
 
 
 
 
 
 
 
Change in Fair Value of Plan Assets
 
 
 
 
 
 
 
 
Fair Value of Plan Assets as of January 1,
 
$
498.5

 
$
501.6

 
$
206.2

 
$
212.0

Actual Gain (Loss) on Plan Assets
 
2.2

 
21.7

 
(2.6
)
 
6.0

Company Contributions
 
7.7

 
6.6

 
—

 
—

Participant Contributions
 
—

 
—

 
4.3

 
5.6

Benefit Payments
 
(36.3
)
 
(31.4
)
 
(16.3
)
 
(17.4
)
Fair Value of Plan Assets as of December 31,
 
$
472.1

 
$
498.5

 
$
191.6

 
$
206.2

 
 
 
 
 
 
 
 
 
Funded (Underfunded) Status as of December 31,
 
$
(25.4
)
 
$
(27.8
)
 
$
23.0

 
$
41.5
Benefit Amounts Recognized on the Balance Sheets
 
 
Pension Plans
 
Other Postretirement
Benefit Plans
 
 
December 31,
OPCo
 
2015
 
2014
 
2015
 
2014
 
 
(in millions)
Deferred Charges and Other Noncurrent Assets – Prepaid Benefit Costs
 
$
—

 
$
—

 
$
23.0

 
$
41.5

Employee Benefits and Pension Obligations – Accrued Long-term Benefit Liability
 
(25.4
)
 
(27.8
)
 
—

 
—

Funded (Underfunded) Status
 
$
(25.4
)
 
$
(27.8
)
 
$
23.0

 
$
41.5
Amounts Included in AOCI and Regulatory Assets
OPCo
 
Pension Plans
 
Other Postretirement
Benefit Plans
 
 
December 31,
 
 
2015
 
2014
 
2015
 
2014
Components
 
(in millions)
Net Actuarial Loss
 
$
222.0

 
$
226.7

 
$
52.6

 
$
30.7

Prior Service Cost (Credit)
 
0.2

 
0.4

 
(55.4
)
 
(62.4
)
 
 
 
 
 
 
 
 
 
Recorded as
 
 
 
 
 
 
 
 
Regulatory Assets
 
$
222.2

 
$
227.1

 
$
(2.8
)
 
$
(31.7
)
Components of Change in Amounts Included in AOCI and Regulatory Assets
OPCo
 
Pension Plans
 
Other Postretirement
Benefit Plans
 
 
2015
 
2014
 
2015
 
2014
Components
 
(in millions)
Actuarial Loss During the Year
 
$
5.8

 
$
11.5

 
$
24.0

 
$
3.3

Amortization of Actuarial Loss
 
(10.5
)
 
(12.4
)
 
(2.1
)
 
(2.4
)
Amortization of Prior Service Credit (Cost)
 
(0.2
)
 
(0.2
)
 
7.0

 
6.9

Change for the Year Ended December 31,
 
$
(4.9
)
 
$
(1.1
)
 
$
28.9

 
$
7.8
Allocated Assets of Investments
 
 
Pension Plan
 
Other Postretirement
Benefit Plans
Company
 
2015
 
2014
 
2015
 
2014
APCo
 
12.7
%
 
12.9
%
 
16.3
%
 
16.6
%
I&M
 
12.0
%
 
11.9
%
 
12.0
%
 
11.9
%
OPCo
 
9.9
%
 
10.0
%
 
12.1
%
 
12.2
%
PSO
 
5.5
%
 
5.5
%
 
5.6
%
 
5.7
%
SWEPCo
 
5.9
%
 
5.8
%
 
6.2
%
 
6.3
%
Accumulated Benefit Obligation
Accumulated Benefit Obligation
 
AEP
 
APCo
 
I&M
 
OPCo
 
PSO
 
SWEPCo
 
 
(in millions)
Qualified Pension Plan
 
$
4,757.1

 
$
641.4

 
$
571.3

 
$
484.1

 
$
252.0

 
$
267.7

Nonqualified Pension Plans
 
75.6

 
0.5

 
0.4

 
0.1

 
2.4

 
1.6

Total as of December 31, 2015
 
$
4,832.7

 
$
641.9

 
$
571.7

 
$
484.2

 
$
254.4

 
$
269.3

 
 
 
 
 
 
 
 
 
 
 
 
 
Accumulated Benefit Obligation
 
AEP
 
APCo
 
I&M
 
OPCo
 
PSO
 
SWEPCo
 
 
(in millions)
Qualified Pension Plan
 
$
4,982.0

 
$
688.6

 
$
598.2

 
$
512.4

 
$
270.0

 
$
281.2

Nonqualified Pension Plans
 
76.0

 
0.5

 
0.5

 
0.1

 
2.8

 
1.8

Total as of December 31, 2014
 
$
5,058.0

 
$
689.1

 
$
598.7

 
$
512.5

 
$
272.8

 
$
283.0
Underfunded Accumulated Benefit Obligation
 
AEP
 
APCo
 
I&M
 
OPCo
 
PSO
 
SWEPCo
 
(in millions)
Projected Benefit Obligation
$
4,992.9

 
$
653.4

 
$
591.5

 
$
497.5

 
$
2.6

 
$
1.7

 
 
 
 
 
 
 
 
 
 
 
 
Accumulated Benefit Obligation
$
4,832.7

 
$
641.9

 
$
571.7

 
$
484.2

 
$
2.4

 
$
1.6

Fair Value of Plan Assets
4,767.6

 
603.2

 
570.0

 
472.1

 
—

 
—

Underfunded Accumulated Benefit Obligation as of December 31, 2015
$
(65.1
)
 
$
(38.7
)
 
$
(1.7
)
 
$
(12.1
)
 
$
(2.4
)
 
$
(1.6
)
 
 
 
 
 
 
 
 
 
 
 
 
 
AEP
 
APCo
 
I&M
 
OPCo
 
PSO
 
SWEPCo
 
(in millions)
Projected Benefit Obligation
$
5,224.9

 
$
702.8

 
$
617.9

 
$
526.3

 
$
2.8

 
$
1.8

 
 
 
 
 
 
 
 
 
 
 
 
Accumulated Benefit Obligation
$
5,058.0

 
$
689.1

 
$
598.7

 
$
512.5

 
$
2.8

 
$
1.8

Fair Value of Plan Assets
4,967.5

 
642.3

 
591.7

 
498.5

 
—

 
—

Underfunded Accumulated Benefit Obligation as of December 31, 2014
$
(90.5
)
 
$
(46.8
)
 
$
(7.0
)
 
$
(14.0
)
 
$
(2.8
)
 
$
(1.8
)
Estimated Contributions and Payments to the Pension and OPEB Plans
Company
 
Pension Plans
 
Other Postretirement
Benefit Plans
 
 
(in millions)
AEP
 
$
95.6

 
$
6.0

APCo
 
10.7

 
2.6

I&M
 
13.1

 
—

OPCo
 
7.5

 
—

PSO
 
5.7

 
—

SWEPCo
 
6.9

 
—
Estimated Payments Expected to be Made by the Pension and OPEB Plans
Pension Plans
 
AEP
 
APCo
 
I&M
 
OPCo
 
PSO
 
SWEPCo
 
 
(in millions)
2016
 
$
324.0

 
$
42.8

 
$
33.9

 
$
36.4

 
$
19.3

 
$
18.6

2017
 
335.5

 
43.2

 
35.6

 
36.0

 
20.2

 
20.2

2018
 
339.3

 
44.2

 
36.0

 
35.8

 
20.1

 
21.1

2019
 
348.7

 
44.6

 
38.6

 
36.1

 
20.9

 
21.8

2020
 
355.9

 
45.0

 
39.3

 
36.2

 
21.3

 
22.4

Years 2021 to 2025, in Total
 
1,844.3

 
232.3

 
213.1

 
174.3

 
109.1

 
120.2

 
Other Postretirement Benefit Plans:
Benefit Payments
 
AEP
 
APCo
 
I&M
 
OPCo
 
PSO
 
SWEPCo
 
 
(in millions)
2016
 
$
134.1

 
$
25.3

 
$
15.9

 
$
16.9

 
$
7.4

 
$
7.9

2017
 
136.7

 
25.4

 
16.2

 
17.1

 
7.6

 
8.1

2018
 
139.1

 
25.6

 
16.6

 
17.3

 
7.7

 
8.3

2019
 
140.3

 
25.3

 
16.8

 
17.3

 
7.9

 
8.4

2020
 
143.6

 
25.6

 
17.2

 
17.5

 
8.1

 
8.7

Years 2021 to 2025, in Total
 
749.7

 
127.9

 
90.4

 
87.6

 
42.7

 
47.6

Other Postretirement Benefit Plans:
Medicare Subsidy Receipts
 
AEP
 
APCo
 
I&M
 
OPCo
 
PSO
 
SWEPCo
 
 
(in millions)
2016
 
$
0.3

 
$
0.2

 
$
—

 
$
—

 
$
—

 
$
—

2017
 
0.3

 
0.2

 
—

 
—

 
—

 
—

2018
 
0.3

 
0.2

 
—

 
—

 
—

 
—

2019
 
0.3

 
0.2

 
—

 
—

 
—

 
—

2020
 
0.3

 
0.2

 
—

 
—

 
—

 
—

Years 2021 to 2025, in Total
 
1.8

 
1.1

 
—

 
—

 
—

 
—
Components of Net Periodic Benefit Cost
OPCo
Pension Plans
 
Other Postretirement
Benefit Plans
 
Years Ended December 31,
 
2015
 
2014
 
2013
 
2015
 
2014
 
2013
 
(in millions)
Service Cost
$
6.7

 
$
5.2

 
$
5.3

 
$
0.9

 
$
1.0

 
$
2.9

Interest Cost
20.3

 
22.1

 
21.9

 
6.4

 
7.6

 
9.5

Expected Return on Plan Assets
(27.5
)
 
(26.5
)
 
(29.9
)
 
(13.4
)
 
(13.5
)
 
(13.5
)
Amortization of Prior Service Cost (Credit)
0.2

 
0.2

 
0.2

 
(7.0
)
 
(6.9
)
 
(6.9
)
Amortization of Net Actuarial Loss
10.5

 
12.4

 
19.8

 
2.1

 
2.4

 
8.6

Net Periodic Benefit Cost (Credit)
10.2

 
13.4

 
17.3

 
(11.0
)
 
(9.4
)
 
0.6

Capitalized Portion
(4.8
)
 
(5.5
)
 
(6.2
)
 
5.2

 
3.8

 
(0.2
)
Net Periodic Benefit Cost (Credit) Recognized in Expense
$
5.4

 
$
7.9

 
$
11.1

 
$
(5.8
)
 
$
(5.6
)
 
$
0.4
Estimated Amounts to be Amortized to Net Periodic Benefit Costs
 
 
AEP
 
APCo
 
I&M
 
OPCo
 
PSO
 
SWEPCo
Pension Plans – Components
 
(in millions)
Net Actuarial Loss
 
$
82.9

 
$
10.7

 
$
9.7

 
$
8.2

 
$
4.4

 
$
4.7

Prior Service Cost
 
2.2

 
0.2

 
0.2

 
0.1

 
0.2

 
0.3

Total Estimated 2016 Amortization
 
$
85.1

 
$
10.9

 
$
9.9

 
$
8.3

 
$
4.6

 
$
5.0

 
 
 
 
 
 
 
 
 
 
 
 
 
Pension Plans –
Expected to be Recorded as
 
 
 
 
 
 
 
 
 
 
 
 
Regulatory Asset
 
$
73.8

 
$
10.9

 
$
9.3

 
$
8.3

 
$
4.6

 
$
5.0

Deferred Income Taxes
 
3.9

 
—

 
0.2

 
—

 
—

 
—

Net of Tax AOCI
 
7.4

 
—

 
0.4

 
—

 
—

 
—

Total
 
$
85.1

 
$
10.9

 
$
9.9

 
$
8.3

 
$
4.6

 
$
5.0

 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
AEP
 
APCo
 
I&M
 
OPCo
 
PSO
 
SWEPCo
Other Postretirement Benefit Plans –
Components
 
(in millions)
Net Actuarial Loss
 
$
29.8

 
$
5.2

 
$
3.5

 
$
3.6

 
$
1.7

 
$
1.8

Prior Service Credit
 
(69.0
)
 
(10.1
)
 
(9.4
)
 
(6.9
)
 
(4.3
)
 
(5.1
)
Total Estimated 2016 Amortization
 
$
(39.2
)
 
$
(4.9
)
 
$
(5.9
)
 
$
(3.3
)
 
$
(2.6
)
 
$
(3.3
)
 
 
 
 
 
 
 
 
 
 
 
 
 
Other Postretirement Benefit Plans –
Expected to be Recorded as
 
 
 
 
 
 
 
 
 
 
 
 
Regulatory Asset
 
$
(28.5
)
 
$
(2.6
)
 
$
(5.3
)
 
$
(3.3
)
 
$
(2.6
)
 
$
(2.1
)
Deferred Income Taxes
 
(3.7
)
 
(0.8
)
 
(0.2
)
 
—

 
—

 
(0.4
)
Net of Tax AOCI
 
(7.0
)
 
(1.5
)
 
(0.4
)
 
—

 
—

 
(0.8
)
Total
 
$
(39.2
)
 
$
(4.9
)
 
$
(5.9
)
 
$
(3.3
)
 
$
(2.6
)
 
$
(3.3
)
Cost for Matching Contributions to the Retirement Savings Plans
 
 
Year Ended December 31,
Company
 
2015
 
2014
 
2013
 
 
(in millions)
AEP
 
$
73.6

 
$
70.5

 
$
66.6

APCo
 
7.2

 
7.3

 
7.4

I&M
 
10.6

 
10.5

 
10.0

OPCo
 
5.4

 
5.2

 
6.5

PSO
 
4.2

 
4.0

 
3.8

SWEPCo
 
5.7

 
5.3

 
5.0
Public Service Co Of Oklahoma [Member]  
Health Care Trend Rates
Health Care Trend Rates
 
2015
 
2014
Initial
 
6.25
%
 
6.50
%
Ultimate
 
5.00
%
 
5.00
%
Year Ultimate Reached
 
2020

 
2020
Effect of a 1% Change in Assumed Health Care Cost Trend Rates for the OPEB Health Care Plans
 
 
AEP
 
APCo
 
I&M
 
OPCo
 
PSO
 
SWEPCo
 
 
(in millions)
Effect on Total Service and Interest Cost Components of Net Periodic Postretirement Health Care Benefit Cost:
 
 
 
 
 
 
 
 
 
 
 
 
1% Increase
 
$
3.7

 
$
0.8

 
$
0.3

 
$
0.3

 
$
0.1

 
$
0.2

1% Decrease
 
(3.0
)
 
(0.6
)
 
(0.3
)
 
(0.2
)
 
(0.1
)
 
(0.1
)
 
 
 
 
 
 
 
 
 
 
 
 
 
Effect on the Health Care Component of the Accumulated Postretirement Benefit Obligation:
 
 
 
 
 
 
 
 
 
 
 
 
1% Increase
 
$
70.5

 
$
15.2

 
$
6.8

 
$
6.9

 
$
3.2

 
$
3.5

1% Decrease
 
(57.4
)
 
(12.3
)
 
(5.6
)
 
(5.7
)
 
(2.6
)
 
(2.9
)
Reconciliation of Changes in Benefit Obligations and Fair Value of Assets
PSO
 
Pension Plans
 
Other Postretirement
Benefit Plans
 
 
2015
 
2014
 
2015
 
2014
Change in Benefit Obligation
 
(in millions)
Benefit Obligation as of January 1,
 
$
285.4

 
$
260.7

 
$
76.7

 
$
77.8

Service Cost
 
6.4

 
5.2

 
0.7

 
0.8

Interest Cost
 
10.9

 
12.1

 
3.0

 
3.6

Actuarial (Gain) Loss
 
(17.9
)
 
25.7

 
2.4

 
(1.0
)
Benefit Payments
 
(19.4
)
 
(18.3
)
 
(7.1
)
 
(7.3
)
Participant Contributions
 
—

 
—

 
1.9

 
2.3

Medicare Subsidy
 
—

 
—

 
0.1

 
0.5

Benefit Obligation as of December 31,
 
$
265.4

 
$
285.4

 
$
77.7

 
$
76.7

 
 
 
 
 
 
 
 
 
Change in Fair Value of Plan Assets
 
 
 
 
 
 
 
 
Fair Value of Plan Assets as of January 1,
 
$
275.5

 
$
264.6

 
$
96.0

 
$
96.3

Actual Gain (Loss) on Plan Assets
 
0.1

 
24.6

 
(2.5
)
 
4.7

Company Contributions
 
5.9

 
4.6

 
—

 
—

Participant Contributions
 
—

 
—

 
1.9

 
2.3

Benefit Payments
 
(19.4
)
 
(18.3
)
 
(7.1
)
 
(7.3
)
Fair Value of Plan Assets as of December 31,
 
$
262.1

 
$
275.5

 
$
88.3

 
$
96.0

 
 
 
 
 
 
 
 
 
Funded (Underfunded) Status as of December 31,
 
$
(3.3
)
 
$
(9.9
)
 
$
10.6

 
$
19.3
Benefit Amounts Recognized on the Balance Sheets
 
 
Pension Plans
 
Other Postretirement
Benefit Plans
 
 
December 31,
PSO
 
2015
 
2014
 
2015
 
2014
 
 
(in millions)
Employee Benefits and Pension Assets – Prepaid Benefit Costs
 
$
—

 
$
—

 
$
10.6

 
$
19.3

Other Current Liabilities – Accrued Short-term Benefit Liability
 
(0.2
)
 
(0.2
)
 
—

 
—

Employee Benefits and Pension Obligations – Accrued Long-term Benefit Liability
 
(3.1
)
 
(9.7
)
 
—

 
—

Funded (Underfunded) Status
 
$
(3.3
)
 
$
(9.9
)
 
$
10.6

 
$
19.3
Amounts Included in AOCI and Regulatory Assets
PSO
 
Pension Plans
 
Other Postretirement
Benefit Plans
 
 
December 31,
 
 
2015
 
2014
 
2015
 
2014
Components
 
(in millions)
Net Actuarial Loss
 
$
94.1

 
$
102.7

 
$
35.2

 
$
25.3

Prior Service Cost (Credit)
 
0.3

 
0.5

 
(34.5
)
 
(38.8
)
 
 
 
 
 
 
 
 
 
Recorded as
 
 
 
 
 
 
 
 
Regulatory Assets
 
$
94.4

 
$
103.2

 
$
0.7

 
$
(13.5
)
Components of Change in Amounts Included in AOCI and Regulatory Assets
PSO
 
Pension Plans
 
Other Postretirement
Benefit Plans
 
 
2015
 
2014
 
2015
 
2014
Components
 
(in millions)
Actuarial (Gain) Loss During the Year
 
$
(2.9
)
 
$
15.7

 
$
10.9

 
$
0.6

Amortization of Actuarial Loss
 
(5.7
)
 
(6.7
)
 
(1.0
)
 
(1.1
)
Amortization of Prior Service Credit (Cost)
 
(0.2
)
 
(0.3
)
 
4.3

 
4.3

Change for the Year Ended December 31,
 
$
(8.8
)
 
$
8.7

 
$
14.2

 
$
3.8
Allocated Assets of Investments
 
 
Pension Plan
 
Other Postretirement
Benefit Plans
Company
 
2015
 
2014
 
2015
 
2014
APCo
 
12.7
%
 
12.9
%
 
16.3
%
 
16.6
%
I&M
 
12.0
%
 
11.9
%
 
12.0
%
 
11.9
%
OPCo
 
9.9
%
 
10.0
%
 
12.1
%
 
12.2
%
PSO
 
5.5
%
 
5.5
%
 
5.6
%
 
5.7
%
SWEPCo
 
5.9
%
 
5.8
%
 
6.2
%
 
6.3
%
Accumulated Benefit Obligation
Accumulated Benefit Obligation
 
AEP
 
APCo
 
I&M
 
OPCo
 
PSO
 
SWEPCo
 
 
(in millions)
Qualified Pension Plan
 
$
4,757.1

 
$
641.4

 
$
571.3

 
$
484.1

 
$
252.0

 
$
267.7

Nonqualified Pension Plans
 
75.6

 
0.5

 
0.4

 
0.1

 
2.4

 
1.6

Total as of December 31, 2015
 
$
4,832.7

 
$
641.9

 
$
571.7

 
$
484.2

 
$
254.4

 
$
269.3

 
 
 
 
 
 
 
 
 
 
 
 
 
Accumulated Benefit Obligation
 
AEP
 
APCo
 
I&M
 
OPCo
 
PSO
 
SWEPCo
 
 
(in millions)
Qualified Pension Plan
 
$
4,982.0

 
$
688.6

 
$
598.2

 
$
512.4

 
$
270.0

 
$
281.2

Nonqualified Pension Plans
 
76.0

 
0.5

 
0.5

 
0.1

 
2.8

 
1.8

Total as of December 31, 2014
 
$
5,058.0

 
$
689.1

 
$
598.7

 
$
512.5

 
$
272.8

 
$
283.0
Underfunded Accumulated Benefit Obligation
 
AEP
 
APCo
 
I&M
 
OPCo
 
PSO
 
SWEPCo
 
(in millions)
Projected Benefit Obligation
$
4,992.9

 
$
653.4

 
$
591.5

 
$
497.5

 
$
2.6

 
$
1.7

 
 
 
 
 
 
 
 
 
 
 
 
Accumulated Benefit Obligation
$
4,832.7

 
$
641.9

 
$
571.7

 
$
484.2

 
$
2.4

 
$
1.6

Fair Value of Plan Assets
4,767.6

 
603.2

 
570.0

 
472.1

 
—

 
—

Underfunded Accumulated Benefit Obligation as of December 31, 2015
$
(65.1
)
 
$
(38.7
)
 
$
(1.7
)
 
$
(12.1
)
 
$
(2.4
)
 
$
(1.6
)
 
 
 
 
 
 
 
 
 
 
 
 
 
AEP
 
APCo
 
I&M
 
OPCo
 
PSO
 
SWEPCo
 
(in millions)
Projected Benefit Obligation
$
5,224.9

 
$
702.8

 
$
617.9

 
$
526.3

 
$
2.8

 
$
1.8

 
 
 
 
 
 
 
 
 
 
 
 
Accumulated Benefit Obligation
$
5,058.0

 
$
689.1

 
$
598.7

 
$
512.5

 
$
2.8

 
$
1.8

Fair Value of Plan Assets
4,967.5

 
642.3

 
591.7

 
498.5

 
—

 
—

Underfunded Accumulated Benefit Obligation as of December 31, 2014
$
(90.5
)
 
$
(46.8
)
 
$
(7.0
)
 
$
(14.0
)
 
$
(2.8
)
 
$
(1.8
)
Estimated Contributions and Payments to the Pension and OPEB Plans
Company
 
Pension Plans
 
Other Postretirement
Benefit Plans
 
 
(in millions)
AEP
 
$
95.6

 
$
6.0

APCo
 
10.7

 
2.6

I&M
 
13.1

 
—

OPCo
 
7.5

 
—

PSO
 
5.7

 
—

SWEPCo
 
6.9

 
—
Estimated Payments Expected to be Made by the Pension and OPEB Plans
Pension Plans
 
AEP
 
APCo
 
I&M
 
OPCo
 
PSO
 
SWEPCo
 
 
(in millions)
2016
 
$
324.0

 
$
42.8

 
$
33.9

 
$
36.4

 
$
19.3

 
$
18.6

2017
 
335.5

 
43.2

 
35.6

 
36.0

 
20.2

 
20.2

2018
 
339.3

 
44.2

 
36.0

 
35.8

 
20.1

 
21.1

2019
 
348.7

 
44.6

 
38.6

 
36.1

 
20.9

 
21.8

2020
 
355.9

 
45.0

 
39.3

 
36.2

 
21.3

 
22.4

Years 2021 to 2025, in Total
 
1,844.3

 
232.3

 
213.1

 
174.3

 
109.1

 
120.2

 
Other Postretirement Benefit Plans:
Benefit Payments
 
AEP
 
APCo
 
I&M
 
OPCo
 
PSO
 
SWEPCo
 
 
(in millions)
2016
 
$
134.1

 
$
25.3

 
$
15.9

 
$
16.9

 
$
7.4

 
$
7.9

2017
 
136.7

 
25.4

 
16.2

 
17.1

 
7.6

 
8.1

2018
 
139.1

 
25.6

 
16.6

 
17.3

 
7.7

 
8.3

2019
 
140.3

 
25.3

 
16.8

 
17.3

 
7.9

 
8.4

2020
 
143.6

 
25.6

 
17.2

 
17.5

 
8.1

 
8.7

Years 2021 to 2025, in Total
 
749.7

 
127.9

 
90.4

 
87.6

 
42.7

 
47.6

Other Postretirement Benefit Plans:
Medicare Subsidy Receipts
 
AEP
 
APCo
 
I&M
 
OPCo
 
PSO
 
SWEPCo
 
 
(in millions)
2016
 
$
0.3

 
$
0.2

 
$
—

 
$
—

 
$
—

 
$
—

2017
 
0.3

 
0.2

 
—

 
—

 
—

 
—

2018
 
0.3

 
0.2

 
—

 
—

 
—

 
—

2019
 
0.3

 
0.2

 
—

 
—

 
—

 
—

2020
 
0.3

 
0.2

 
—

 
—

 
—

 
—

Years 2021 to 2025, in Total
 
1.8

 
1.1

 
—

 
—

 
—

 
—
Components of Net Periodic Benefit Cost
PSO
Pension Plans
 
Other Postretirement
Benefit Plans
 
Years Ended December 31,
 
2015
 
2014
 
2013
 
2015
 
2014
 
2013
 
(in millions)
Service Cost
$
6.4

 
$
5.2

 
$
5.6

 
$
0.7

 
$
0.8

 
$
1.4

Interest Cost
10.9

 
12.1

 
11.0

 
3.0

 
3.6

 
3.8

Expected Return on Plan Assets
(15.1
)
 
(14.6
)
 
(15.7
)
 
(6.3
)
 
(6.3
)
 
(6.1
)
Amortization of Prior Service Cost (Credit)
0.2

 
0.3

 
0.3

 
(4.3
)
 
(4.3
)
 
(4.3
)
Amortization of Net Actuarial Loss
5.7

 
6.7

 
9.8

 
1.0

 
1.1

 
3.5

Net Periodic Benefit Cost (Credit)
8.1

 
9.7

 
11.0

 
(5.9
)
 
(5.1
)
 
(1.7
)
Capitalized Portion
(2.8
)
 
(3.3
)
 
(3.4
)
 
2.0

 
1.7

 
0.5

Net Periodic Benefit Cost (Credit) Recognized in Expense
$
5.3

 
$
6.4

 
$
7.6

 
$
(3.9
)
 
$
(3.4
)
 
$
(1.2
)
Estimated Amounts to be Amortized to Net Periodic Benefit Costs
 
 
AEP
 
APCo
 
I&M
 
OPCo
 
PSO
 
SWEPCo
Pension Plans – Components
 
(in millions)
Net Actuarial Loss
 
$
82.9

 
$
10.7

 
$
9.7

 
$
8.2

 
$
4.4

 
$
4.7

Prior Service Cost
 
2.2

 
0.2

 
0.2

 
0.1

 
0.2

 
0.3

Total Estimated 2016 Amortization
 
$
85.1

 
$
10.9

 
$
9.9

 
$
8.3

 
$
4.6

 
$
5.0

 
 
 
 
 
 
 
 
 
 
 
 
 
Pension Plans –
Expected to be Recorded as
 
 
 
 
 
 
 
 
 
 
 
 
Regulatory Asset
 
$
73.8

 
$
10.9

 
$
9.3

 
$
8.3

 
$
4.6

 
$
5.0

Deferred Income Taxes
 
3.9

 
—

 
0.2

 
—

 
—

 
—

Net of Tax AOCI
 
7.4

 
—

 
0.4

 
—

 
—

 
—

Total
 
$
85.1

 
$
10.9

 
$
9.9

 
$
8.3

 
$
4.6

 
$
5.0

 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
AEP
 
APCo
 
I&M
 
OPCo
 
PSO
 
SWEPCo
Other Postretirement Benefit Plans –
Components
 
(in millions)
Net Actuarial Loss
 
$
29.8

 
$
5.2

 
$
3.5

 
$
3.6

 
$
1.7

 
$
1.8

Prior Service Credit
 
(69.0
)
 
(10.1
)
 
(9.4
)
 
(6.9
)
 
(4.3
)
 
(5.1
)
Total Estimated 2016 Amortization
 
$
(39.2
)
 
$
(4.9
)
 
$
(5.9
)
 
$
(3.3
)
 
$
(2.6
)
 
$
(3.3
)
 
 
 
 
 
 
 
 
 
 
 
 
 
Other Postretirement Benefit Plans –
Expected to be Recorded as
 
 
 
 
 
 
 
 
 
 
 
 
Regulatory Asset
 
$
(28.5
)
 
$
(2.6
)
 
$
(5.3
)
 
$
(3.3
)
 
$
(2.6
)
 
$
(2.1
)
Deferred Income Taxes
 
(3.7
)
 
(0.8
)
 
(0.2
)
 
—

 
—

 
(0.4
)
Net of Tax AOCI
 
(7.0
)
 
(1.5
)
 
(0.4
)
 
—

 
—

 
(0.8
)
Total
 
$
(39.2
)
 
$
(4.9
)
 
$
(5.9
)
 
$
(3.3
)
 
$
(2.6
)
 
$
(3.3
)
Cost for Matching Contributions to the Retirement Savings Plans
 
 
Year Ended December 31,
Company
 
2015
 
2014
 
2013
 
 
(in millions)
AEP
 
$
73.6

 
$
70.5

 
$
66.6

APCo
 
7.2

 
7.3

 
7.4

I&M
 
10.6

 
10.5

 
10.0

OPCo
 
5.4

 
5.2

 
6.5

PSO
 
4.2

 
4.0

 
3.8

SWEPCo
 
5.7

 
5.3

 
5.0
Southwestern Electric Power Co [Member]  
Health Care Trend Rates
Health Care Trend Rates
 
2015
 
2014
Initial
 
6.25
%
 
6.50
%
Ultimate
 
5.00
%
 
5.00
%
Year Ultimate Reached
 
2020

 
2020
Effect of a 1% Change in Assumed Health Care Cost Trend Rates for the OPEB Health Care Plans
 
 
AEP
 
APCo
 
I&M
 
OPCo
 
PSO
 
SWEPCo
 
 
(in millions)
Effect on Total Service and Interest Cost Components of Net Periodic Postretirement Health Care Benefit Cost:
 
 
 
 
 
 
 
 
 
 
 
 
1% Increase
 
$
3.7

 
$
0.8

 
$
0.3

 
$
0.3

 
$
0.1

 
$
0.2

1% Decrease
 
(3.0
)
 
(0.6
)
 
(0.3
)
 
(0.2
)
 
(0.1
)
 
(0.1
)
 
 
 
 
 
 
 
 
 
 
 
 
 
Effect on the Health Care Component of the Accumulated Postretirement Benefit Obligation:
 
 
 
 
 
 
 
 
 
 
 
 
1% Increase
 
$
70.5

 
$
15.2

 
$
6.8

 
$
6.9

 
$
3.2

 
$
3.5

1% Decrease
 
(57.4
)
 
(12.3
)
 
(5.6
)
 
(5.7
)
 
(2.6
)
 
(2.9
)
Reconciliation of Changes in Benefit Obligations and Fair Value of Assets
SWEPCo
 
Pension Plans
 
Other Postretirement
Benefit Plans
 
 
2015
 
2014
 
2015
 
2014
Change in Benefit Obligation
 
(in millions)
Benefit Obligation as of January 1,
 
$
298.2

 
$
270.6

 
$
85.0

 
$
87.0

Service Cost
 
8.3

 
6.6

 
0.8

 
1.0

Interest Cost
 
11.8

 
12.7

 
3.4

 
4.0

Actuarial (Gain) Loss
 
(16.2
)
 
27.5

 
2.1

 
(2.3
)
Benefit Payments
 
(19.3
)
 
(19.2
)
 
(7.4
)
 
(7.7
)
Participant Contributions
 
—

 
—

 
2.1

 
2.5

Medicare Subsidy
 
—

 
—

 
0.1

 
0.5

Benefit Obligation as of December 31,
 
$
282.8

 
$
298.2

 
$
86.1

 
$
85.0

 
 
 
 
 
 
 
 
 
Change in Fair Value of Plan Assets
 
 
 
 
 
 
 
 
Fair Value of Plan Assets as of January 1,
 
$
290.2

 
$
279.0

 
$
106.4

 
$
107.7

Actual Gain (Loss) on Plan Assets
 
1.6

 
26.5

 
(3.3
)
 
3.9

Company Contributions
 
8.1

 
3.9

 
—

 
—

Participant Contributions
 
—

 
—

 
2.1

 
2.5

Benefit Payments
 
(19.3
)
 
(19.2
)
 
(7.4
)
 
(7.7
)
Fair Value of Plan Assets as of December 31,
 
$
280.6

 
$
290.2

 
$
97.8

 
$
106.4

 
 
 
 
 
 
 
 
 
Funded (Underfunded) Status as of December 31,
 
$
(2.2
)
 
$
(8.0
)
 
$
11.7

 
$
21.4
Benefit Amounts Recognized on the Balance Sheets
 
 
Pension Plans
 
Other Postretirement
Benefit Plans
 
 
December 31,
SWEPCo
 
2015
 
2014
 
2015
 
2014
 
 
(in millions)
Deferred Charges and Other Noncurrent Assets –
Prepaid Benefit Costs
 
$
—

 
$
—

 
$
11.7

 
$
21.4

Other Current Liabilities – Accrued Short-term
Benefit Liability
 
(0.1
)
 
(0.1
)
 
—

 
—

Employee Benefits and Pension Obligations –
Accrued Long-term Benefit Liability
 
(2.1
)
 
(7.9
)
 
—

 
—

Funded (Underfunded) Status
 
$
(2.2
)
 
$
(8.0
)
 
$
11.7

 
$
21.4
Amounts Included in AOCI and Regulatory Assets
SWEPCo
 
Pension Plans
 
Other Postretirement
Benefit Plans
 
 
December 31,
 
 
2015
 
2014
 
2015
 
2014
Components
 
(in millions)
Net Actuarial Loss
 
$
97.1

 
$
104.9

 
$
43.3

 
$
32.4

Prior Service Cost (Credit)
 
0.4

 
0.7

 
(41.6
)
 
(46.8
)
 
 
 
 
 
 
 
 
 
Recorded as
 
 
 
 
 
 
 
 
Regulatory Assets
 
$
97.5

 
$
105.6

 
$
1.2

 
$
(8.9
)
Deferred Income Taxes
 
—

 
—

 
0.2

 
(1.9
)
Net of Tax AOCI
 
—

 
—

 
0.3

 
(3.6
)
Components of Change in Amounts Included in AOCI and Regulatory Assets
SWEPCo
 
Pension Plans
 
Other Postretirement
Benefit Plans
 
 
2015
 
2014
 
2015
 
2014
Components
 
(in millions)
Actuarial (Gain) Loss During the Year
 
$
(1.8
)
 
$
16.5

 
$
12.0

 
$
0.8

Amortization of Actuarial Loss
 
(6.0
)
 
(7.1
)
 
(1.1
)
 
(1.2
)
Amortization of Prior Service Credit (Cost)
 
(0.3
)
 
(0.3
)
 
5.2

 
5.2

Change for the Year Ended December 31,
 
$
(8.1
)
 
$
9.1

 
$
16.1

 
$
4.8
Allocated Assets of Investments
 
 
Pension Plan
 
Other Postretirement
Benefit Plans
Company
 
2015
 
2014
 
2015
 
2014
APCo
 
12.7
%
 
12.9
%
 
16.3
%
 
16.6
%
I&M
 
12.0
%
 
11.9
%
 
12.0
%
 
11.9
%
OPCo
 
9.9
%
 
10.0
%
 
12.1
%
 
12.2
%
PSO
 
5.5
%
 
5.5
%
 
5.6
%
 
5.7
%
SWEPCo
 
5.9
%
 
5.8
%
 
6.2
%
 
6.3
%
Accumulated Benefit Obligation
Accumulated Benefit Obligation
 
AEP
 
APCo
 
I&M
 
OPCo
 
PSO
 
SWEPCo
 
 
(in millions)
Qualified Pension Plan
 
$
4,757.1

 
$
641.4

 
$
571.3

 
$
484.1

 
$
252.0

 
$
267.7

Nonqualified Pension Plans
 
75.6

 
0.5

 
0.4

 
0.1

 
2.4

 
1.6

Total as of December 31, 2015
 
$
4,832.7

 
$
641.9

 
$
571.7

 
$
484.2

 
$
254.4

 
$
269.3

 
 
 
 
 
 
 
 
 
 
 
 
 
Accumulated Benefit Obligation
 
AEP
 
APCo
 
I&M
 
OPCo
 
PSO
 
SWEPCo
 
 
(in millions)
Qualified Pension Plan
 
$
4,982.0

 
$
688.6

 
$
598.2

 
$
512.4

 
$
270.0

 
$
281.2

Nonqualified Pension Plans
 
76.0

 
0.5

 
0.5

 
0.1

 
2.8

 
1.8

Total as of December 31, 2014
 
$
5,058.0

 
$
689.1

 
$
598.7

 
$
512.5

 
$
272.8

 
$
283.0
Underfunded Accumulated Benefit Obligation
 
AEP
 
APCo
 
I&M
 
OPCo
 
PSO
 
SWEPCo
 
(in millions)
Projected Benefit Obligation
$
4,992.9

 
$
653.4

 
$
591.5

 
$
497.5

 
$
2.6

 
$
1.7

 
 
 
 
 
 
 
 
 
 
 
 
Accumulated Benefit Obligation
$
4,832.7

 
$
641.9

 
$
571.7

 
$
484.2

 
$
2.4

 
$
1.6

Fair Value of Plan Assets
4,767.6

 
603.2

 
570.0

 
472.1

 
—

 
—

Underfunded Accumulated Benefit Obligation as of December 31, 2015
$
(65.1
)
 
$
(38.7
)
 
$
(1.7
)
 
$
(12.1
)
 
$
(2.4
)
 
$
(1.6
)
 
 
 
 
 
 
 
 
 
 
 
 
 
AEP
 
APCo
 
I&M
 
OPCo
 
PSO
 
SWEPCo
 
(in millions)
Projected Benefit Obligation
$
5,224.9

 
$
702.8

 
$
617.9

 
$
526.3

 
$
2.8

 
$
1.8

 
 
 
 
 
 
 
 
 
 
 
 
Accumulated Benefit Obligation
$
5,058.0

 
$
689.1

 
$
598.7

 
$
512.5

 
$
2.8

 
$
1.8

Fair Value of Plan Assets
4,967.5

 
642.3

 
591.7

 
498.5

 
—

 
—

Underfunded Accumulated Benefit Obligation as of December 31, 2014
$
(90.5
)
 
$
(46.8
)
 
$
(7.0
)
 
$
(14.0
)
 
$
(2.8
)
 
$
(1.8
)
Estimated Contributions and Payments to the Pension and OPEB Plans
Company
 
Pension Plans
 
Other Postretirement
Benefit Plans
 
 
(in millions)
AEP
 
$
95.6

 
$
6.0

APCo
 
10.7

 
2.6

I&M
 
13.1

 
—

OPCo
 
7.5

 
—

PSO
 
5.7

 
—

SWEPCo
 
6.9

 
—
Estimated Payments Expected to be Made by the Pension and OPEB Plans
Pension Plans
 
AEP
 
APCo
 
I&M
 
OPCo
 
PSO
 
SWEPCo
 
 
(in millions)
2016
 
$
324.0

 
$
42.8

 
$
33.9

 
$
36.4

 
$
19.3

 
$
18.6

2017
 
335.5

 
43.2

 
35.6

 
36.0

 
20.2

 
20.2

2018
 
339.3

 
44.2

 
36.0

 
35.8

 
20.1

 
21.1

2019
 
348.7

 
44.6

 
38.6

 
36.1

 
20.9

 
21.8

2020
 
355.9

 
45.0

 
39.3

 
36.2

 
21.3

 
22.4

Years 2021 to 2025, in Total
 
1,844.3

 
232.3

 
213.1

 
174.3

 
109.1

 
120.2

 
Other Postretirement Benefit Plans:
Benefit Payments
 
AEP
 
APCo
 
I&M
 
OPCo
 
PSO
 
SWEPCo
 
 
(in millions)
2016
 
$
134.1

 
$
25.3

 
$
15.9

 
$
16.9

 
$
7.4

 
$
7.9

2017
 
136.7

 
25.4

 
16.2

 
17.1

 
7.6

 
8.1

2018
 
139.1

 
25.6

 
16.6

 
17.3

 
7.7

 
8.3

2019
 
140.3

 
25.3

 
16.8

 
17.3

 
7.9

 
8.4

2020
 
143.6

 
25.6

 
17.2

 
17.5

 
8.1

 
8.7

Years 2021 to 2025, in Total
 
749.7

 
127.9

 
90.4

 
87.6

 
42.7

 
47.6

Other Postretirement Benefit Plans:
Medicare Subsidy Receipts
 
AEP
 
APCo
 
I&M
 
OPCo
 
PSO
 
SWEPCo
 
 
(in millions)
2016
 
$
0.3

 
$
0.2

 
$
—

 
$
—

 
$
—

 
$
—

2017
 
0.3

 
0.2

 
—

 
—

 
—

 
—

2018
 
0.3

 
0.2

 
—

 
—

 
—

 
—

2019
 
0.3

 
0.2

 
—

 
—

 
—

 
—

2020
 
0.3

 
0.2

 
—

 
—

 
—

 
—

Years 2021 to 2025, in Total
 
1.8

 
1.1

 
—

 
—

 
—

 
—
Components of Net Periodic Benefit Cost
SWEPCo
Pension Plans
 
Other Postretirement
Benefit Plans
 
Years Ended December 31,
 
2015
 
2014
 
2013
 
2015
 
2014
 
2013
 
(in millions)
Service Cost
$
8.3

 
$
6.6

 
$
7.0

 
$
0.8

 
$
1.0

 
$
1.7

Interest Cost
11.8

 
12.7

 
11.5

 
3.4

 
4.0

 
4.3

Expected Return on Plan Assets
(16.0
)
 
(15.4
)
 
(16.5
)
 
(6.9
)
 
(7.0
)
 
(6.9
)
Amortization of Prior Service Cost (Credit)
0.3

 
0.3

 
0.3

 
(5.2
)
 
(5.2
)
 
(5.1
)
Amortization of Net Actuarial Loss
6.0

 
7.1

 
10.2

 
1.1

 
1.2

 
3.9

Net Periodic Benefit Cost (Credit)
10.4

 
11.3

 
12.5

 
(6.8
)
 
(6.0
)
 
(2.1
)
Capitalized Portion
(3.2
)
 
(3.4
)
 
(3.5
)
 
2.1

 
1.8

 
0.6

Net Periodic Benefit Cost (Credit) Recognized in Expense
$
7.2

 
$
7.9

 
$
9.0

 
$
(4.7
)
 
$
(4.2
)
 
$
(1.5
)
Estimated Amounts to be Amortized to Net Periodic Benefit Costs
 
 
AEP
 
APCo
 
I&M
 
OPCo
 
PSO
 
SWEPCo
Pension Plans – Components
 
(in millions)
Net Actuarial Loss
 
$
82.9

 
$
10.7

 
$
9.7

 
$
8.2

 
$
4.4

 
$
4.7

Prior Service Cost
 
2.2

 
0.2

 
0.2

 
0.1

 
0.2

 
0.3

Total Estimated 2016 Amortization
 
$
85.1

 
$
10.9

 
$
9.9

 
$
8.3

 
$
4.6

 
$
5.0

 
 
 
 
 
 
 
 
 
 
 
 
 
Pension Plans –
Expected to be Recorded as
 
 
 
 
 
 
 
 
 
 
 
 
Regulatory Asset
 
$
73.8

 
$
10.9

 
$
9.3

 
$
8.3

 
$
4.6

 
$
5.0

Deferred Income Taxes
 
3.9

 
—

 
0.2

 
—

 
—

 
—

Net of Tax AOCI
 
7.4

 
—

 
0.4

 
—

 
—

 
—

Total
 
$
85.1

 
$
10.9

 
$
9.9

 
$
8.3

 
$
4.6

 
$
5.0

 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
AEP
 
APCo
 
I&M
 
OPCo
 
PSO
 
SWEPCo
Other Postretirement Benefit Plans –
Components
 
(in millions)
Net Actuarial Loss
 
$
29.8

 
$
5.2

 
$
3.5

 
$
3.6

 
$
1.7

 
$
1.8

Prior Service Credit
 
(69.0
)
 
(10.1
)
 
(9.4
)
 
(6.9
)
 
(4.3
)
 
(5.1
)
Total Estimated 2016 Amortization
 
$
(39.2
)
 
$
(4.9
)
 
$
(5.9
)
 
$
(3.3
)
 
$
(2.6
)
 
$
(3.3
)
 
 
 
 
 
 
 
 
 
 
 
 
 
Other Postretirement Benefit Plans –
Expected to be Recorded as
 
 
 
 
 
 
 
 
 
 
 
 
Regulatory Asset
 
$
(28.5
)
 
$
(2.6
)
 
$
(5.3
)
 
$
(3.3
)
 
$
(2.6
)
 
$
(2.1
)
Deferred Income Taxes
 
(3.7
)
 
(0.8
)
 
(0.2
)
 
—

 
—

 
(0.4
)
Net of Tax AOCI
 
(7.0
)
 
(1.5
)
 
(0.4
)
 
—

 
—

 
(0.8
)
Total
 
$
(39.2
)
 
$
(4.9
)
 
$
(5.9
)
 
$
(3.3
)
 
$
(2.6
)
 
$
(3.3
)
Cost for Matching Contributions to the Retirement Savings Plans
 
 
Year Ended December 31,
Company
 
2015
 
2014
 
2013
 
 
(in millions)
AEP
 
$
73.6

 
$
70.5

 
$
66.6

APCo
 
7.2

 
7.3

 
7.4

I&M
 
10.6

 
10.5

 
10.0

OPCo
 
5.4

 
5.2

 
6.5

PSO
 
4.2

 
4.0

 
3.8

SWEPCo
 
5.7

 
5.3

 
5.0
Pension Plans [Member]  
Assets within Fair Value Hierarchy
Asset Class
 
Level 1
 
Level 2
 
Level 3
 
Other
 
Total
 
Year End
Allocation
 
 
(in millions)
 
 
Equities:
 
 
 
 
 
 
 
 
 
 
 
 
Domestic
 
$
588.6

 
$
—

 
$
—

 
$
—

 
$
588.6

 
11.9
 %
International
 
502.2

 
—

 
—

 
—

 
502.2

 
10.1
 %
Options
 
—

 
14.1

 
—

 
—

 
14.1

 
0.3
 %
Real Estate Investment Trusts
 
54.3

 
—

 
—

 
—

 
54.3

 
1.1
 %
Common Collective Trust – Global
 
—

 
377.0

 
—

 
—

 
377.0

 
7.6
 %
Common Collective Trust – International
 
—

 
18.5

 
—

 
—

 
18.5

 
0.4
 %
Subtotal – Equities
 
1,145.1

 
409.6

 
—

 
—

 
1,554.7

 
31.4
 %
 
 
 
 
 
 
 
 
 
 
 
 
 
Fixed Income:
 
 
 
 
 
 
 
 
 
 
 
 
Common Collective Trust – Debt
 
—

 
30.2

 
—

 
—

 
30.2

 
0.6
 %
United States Government and Agency Securities
 
—

 
449.8

 
—

 
—

 
449.8

 
9.0
 %
Corporate Debt
 
—

 
1,799.5

 
—

 
—

 
1,799.5

 
36.2
 %
Foreign Debt
 
—

 
400.5

 
0.1

 
—

 
400.6

 
8.1
 %
State and Local Government
 
—

 
14.9

 
—

 
—

 
14.9

 
0.3
 %
Other – Asset Backed
 
—

 
29.1

 
—

 
—

 
29.1

 
0.6
 %
Subtotal – Fixed Income
 
—

 
2,724.0

 
0.1

 
—

 
2,724.1

 
54.8
 %
 
 
 
 
 
 
 
 
 
 
 
 
 
Infrastructure
 
—

 
—

 
12.5

 
—

 
12.5

 
0.3
 %
Real Estate
 
—

 
—

 
235.8

 
—

 
235.8

 
4.7
 %
Alternative Investments
 
—

 
—

 
378.9

 
—

 
378.9

 
7.6
 %
Securities Lending
 
—

 
219.8

 
—

 
—

 
219.8

 
4.4
 %
Securities Lending Collateral (a)
 
—

 
—

 
—

 
(221.5
)
 
(221.5
)
 
(4.5
)%
Cash and Cash Equivalents
 
—

 
53.3

 
—

 
—

 
53.3

 
1.1
 %
Other – Pending Transactions and Accrued Income (b)
 
—

 
—

 
—

 
9.9

 
9.9

 
0.2
 %
 
 
 
 
 
 
 
 
 
 
 
 
 
Total
 
$
1,145.1

 
$
3,406.7

 
$
627.3

 
$
(211.6
)
 
$
4,967.5

 
100.0
 %

(a)
Amounts in “Other” column primarily represent an obligation to repay collateral received as part of the Securities Lending Program.
(b)
Amounts in “Other” column primarily represent accrued interest, dividend receivables and transactions pending settlement.
Asset Class
 
Level 1
 
Level 2
 
Level 3
 
Other
 
Total
 
Year End
Allocation
 
 
(in millions)
 
 
Equities:
 
 
 
 
 
 
 
 
 
 
 
 
Domestic
 
$
315.7

 
$
—

 
$
—

 
$
—

 
$
315.7

 
6.6
 %
International
 
402.3

 
—

 
—

 
—

 
402.3

 
8.4
 %
Options
 
—

 
15.6

 
—

 
—

 
15.6

 
0.3
 %
Real Estate Investment Trusts
 
4.0

 
—

 
—

 
—

 
4.0

 
0.1
 %
Common Collective Trust – Global
 
—

 
369.7

 
—

 
—

 
369.7

 
7.8
 %
Common Collective Trust – International
 
—

 
16.1

 
—

 
—

 
16.1

 
0.3
 %
Subtotal – Equities
 
722.0

 
401.4

 
—

 
—

 
1,123.4

 
23.5
 %
 
 
 
 
 
 
 
 
 
 
 
 
 
Fixed Income:
 
 
 
 
 
 
 
 
 
 
 
 
Common Collective Trust – Debt
 
—

 
34.2

 
—

 
—

 
34.2

 
0.7
 %
United States Government and Agency Securities
 
—

 
421.9

 
—

 
—

 
421.9

 
8.9
 %
Corporate Debt
 
—

 
1,983.2

 
—

 
—

 
1,983.2

 
41.6
 %
Foreign Debt
 
—

 
421.4

 
0.1

 
—

 
421.5

 
8.8
 %
State and Local Government
 
—

 
12.8

 
—

 
—

 
12.8

 
0.3
 %
Other – Asset Backed
 
—

 
23.4

 
—

 
—

 
23.4

 
0.5
 %
Subtotal – Fixed Income
 
—

 
2,896.9

 
0.1

 
—

 
2,897.0

 
60.8
 %
 
 
 
 
 
 
 
 
 
 
 
 
 
Infrastructure
 
—

 
—

 
42.0

 
—

 
42.0

 
0.9
 %
Real Estate
 
—

 
—

 
253.7

 
—

 
253.7

 
5.3
 %
Alternative Investments
 
—

 
—

 
378.7

 
—

 
378.7

 
8.0
 %
Securities Lending
 
—

 
263.0

 
—

 
—

 
263.0

 
5.5
 %
Securities Lending Collateral (a)
 
—

 
—

 
—

 
(264.7
)
 
(264.7
)
 
(5.5
)%
Cash and Cash Equivalents
 
—

 
48.6

 
—

 
—

 
48.6

 
1.0
 %
Other – Pending Transactions and Accrued Income (b)
 
—

 
—

 
—

 
25.9

 
25.9

 
0.5
 %
 
 
 
 
 
 
 
 
 
 
 
 
 
Total
 
$
722.0

 
$
3,609.9

 
$
674.5

 
$
(238.8
)
 
$
4,767.6

 
100.0
 %

(a)
Amounts in “Other” column primarily represent an obligation to repay collateral received as part of the Securities Lending Program.
(b)
Amounts in “Other” column primarily represent accrued interest, dividend receivables and transactions pending settlement.
Pension Plan Assets Level 3 Reconciliation
 
 
Foreign Debt
 
Infrastructure
 
Real
Estate
 
Alternative
Investments
 
Total
Level 3
 
 
(in millions)
Balance as of January 1, 2014
 
$
0.1

 
$
—

 
$
238.2

 
$
329.6

 
$
567.9

Actual Return on Plan Assets
 
 
 
 
 
 
 
 
 
 
Relating to Assets Still Held as of the Reporting Date
 
—

 
(0.3
)
 
5.5

 
32.0

 
37.2

Relating to Assets Sold During the Period
 
—

 
0.1

 
19.0

 
15.8

 
34.9

Purchases and Sales
 
—

 
12.7

 
(26.9
)
 
1.5

 
(12.7
)
Transfers into Level 3
 
—

 
—

 
—

 
—

 
—

Transfers out of Level 3
 
—

 
—

 
—

 
—

 
—

Balance as of December 31, 2014
 
$
0.1

 
$
12.5

 
$
235.8

 
$
378.9

 
$
627.3

 
 
Foreign
Debt
 
Infrastructure
 
Real
Estate
 
Alternative
Investments
 
Total
Level 3
 
 
(in millions)
Balance as of January 1, 2015
 
$
0.1

 
$
12.5

 
$
235.8

 
$
378.9

 
$
627.3

Actual Return on Plan Assets
 
 
 
 
 
 
 
 
 
 
Relating to Assets Still Held as of the Reporting Date
 
—

 
(3.6
)
 
12.5

 
(25.9
)
 
(17.0
)
Relating to Assets Sold During the Period
 
—

 
0.3

 
23.8

 
37.6

 
61.7

Purchases and Sales
 
—

 
32.8

 
(18.4
)
 
(11.9
)
 
2.5

Transfers into Level 3
 
—

 
—

 
—

 
—

 
—

Transfers out of Level 3
 
—

 
—

 
—

 
—

 
—

Balance as of December 31, 2015
 
$
0.1

 
$
42.0

 
$
253.7

 
$
378.7

 
$
674.5
Other Postretirement Benefit Plans [Member]  
Assets within Fair Value Hierarchy
Asset Class
 
Level 1
 
Level 2
 
Level 3
 
Other
 
Total
 
Year End
Allocation
 
 
(in millions)
 
 
Equities:
 
 
 
 
 
 
 
 
 
 
 
 
Domestic
 
$
465.1

 
$
—

 
$
—

 
$
—

 
$
465.1

 
29.5
%
International
 
484.3

 
—

 
—

 
—

 
484.3

 
30.7
%
Options
 
—

 
15.6

 
—

 
—

 
15.6

 
1.0
%
Common Collective Trust – Global
 
—

 
19.0

 
—

 
—

 
19.0

 
1.2
%
Common Collective Trust – International
 
—

 
12.6

 
—

 
—

 
12.6

 
0.8
%
Subtotal – Equities
 
949.4

 
47.2

 
—

 
—

 
996.6

 
63.2
%
 
 
 
 
 
 
 
 
 
 
 
 
 
Fixed Income:
 
 
 
 
 
 
 
 
 
 
 
 
Common Collective Trust – Debt
 
—

 
100.9

 
—

 
—

 
100.9

 
6.4
%
United States Government and Agency Securities
 
—

 
58.4

 
—

 
—

 
58.4

 
3.7
%
Corporate Debt
 
—

 
117.7

 
—

 
—

 
117.7

 
7.4
%
Foreign Debt
 
—

 
20.7

 
—

 
—

 
20.7

 
1.3
%
State and Local Government
 
—

 
4.2

 
—

 
—

 
4.2

 
0.3
%
Other – Asset Backed
 
—

 
8.4

 
—

 
—

 
8.4

 
0.5
%
Subtotal – Fixed Income
 
—

 
310.3

 
—

 
—

 
310.3

 
19.6
%
 
 
 
 
 
 
 
 
 
 
 
 
 
Trust Owned Life Insurance:
 
 
 
 
 
 
 
 
 
 
 
 
International Equities
 
—

 
28.3

 
—

 
—

 
28.3

 
1.8
%
United States Bonds
 
—

 
184.3

 
—

 
—

 
184.3

 
11.7
%
Subtotal – Trust Owned Life Insurance
 
—

 
212.6

 
—

 
—

 
212.6

 
13.5
%
 
 
 
 
 
 
 
 
 
 
 
 
 
Cash and Cash Equivalents
 
44.9

 
7.2

 
—

 
—

 
52.1

 
3.3
%
Other – Pending Transactions and Accrued Income (a)
 
—

 
—

 
—

 
5.8

 
5.8

 
0.4
%
 
 
 
 
 
 
 
 
 
 
 
 
 
Total
 
$
994.3

 
$
577.3

 
$
—

 
$
5.8

 
$
1,577.4

 
100.0
%
 

(a)
Amounts in “Other” column primarily represent accrued interest, dividend receivables and transactions pending settlement.
Asset Class
 
Level 1
 
Level 2
 
Level 3
 
Other
 
Total
 
Year End
Allocation
 
 
(in millions)
 
 
Equities:
 
 
 
 
 
 
 
 
 
 
 
 
Domestic
 
$
466.1

 
$
—

 
$
—

 
$
—

 
$
466.1

 
27.5
%
International
 
566.6

 
—

 
—

 
—

 
566.6

 
33.5
%
Options
 
—

 
16.4

 
—

 
—

 
16.4

 
1.0
%
Common Collective Trust – Global
 
—

 
29.6

 
—

 
—

 
29.6

 
1.8
%
Subtotal – Equities
 
1,032.7

 
46.0

 
—

 
—

 
1,078.7

 
63.8
%
 
 
 
 
 
 
 
 
 
 
 
 
 
Fixed Income:
 
 
 
 
 
 
 
 
 
 
 
 
Common Collective Trust – Debt
 
—

 
103.7

 
—

 
—

 
103.7

 
6.1
%
United States Government and Agency Securities
 
—

 
71.1

 
—

 
—

 
71.1

 
4.2
%
Corporate Debt
 
—

 
125.5

 
—

 
—

 
125.5

 
7.4
%
Foreign Debt
 
—

 
21.3

 
—

 
—

 
21.3

 
1.3
%
State and Local Government
 
—

 
5.9

 
—

 
—

 
5.9

 
0.3
%
Other – Asset Backed
 
—

 
4.9

 
—

 
—

 
4.9

 
0.3
%
Subtotal – Fixed Income
 
—

 
332.4

 
—

 
—

 
332.4

 
19.6
%
 
 
 
 
 
 
 
 
 
 
 
 
 
Trust Owned Life Insurance:
 
 
 
 
 
 
 
 
 
 
 
 
International Equities
 
—

 
10.3

 
—

 
—

 
10.3

 
0.6
%
United States Bonds
 
—

 
212.1

 
—

 
—

 
212.1

 
12.5
%
Subtotal – Trust Owned Life Insurance
 
—

 
222.4

 
—

 
—

 
222.4

 
13.1
%
 
 
 
 
 
 
 
 
 
 
 
 
 
Cash and Cash Equivalents
 
46.8

 
9.6

 
—

 
—

 
56.4

 
3.3
%
Other – Pending Transactions and Accrued Income (a)
 
—

 
—

 
—

 
4.0

 
4.0

 
0.2
%
 
 
 
 
 
 
 
 
 
 
 
 
 
Total
 
$
1,079.5

 
$
610.4

 
$
—

 
$
4.0

 
$
1,693.9

 
100.0
%
 

(a)
Amounts in “Other” column primarily represent accrued interest, dividend receivables and transactions pending settlement.
Benefit Obligations [Member]  
Actuarial Assumptions
 
 
Pension Plans
 
Other Postretirement
Benefit Plans
Assumption
 
2015
 
2014
 
2015
 
2014
Discount Rate
 
4.30
%
 
4.00
%
 
4.30
%
 
4.00
%
 
 
Pension Plans
Assumption – Rate of Compensation Increase (a)
 
2015
 
2014
AEP
 
4.80
%
 
4.80
%
APCo
 
4.45
%
 
4.45
%
I&M
 
4.75
%
 
4.80
%
OPCo
 
4.85
%
 
4.80
%
PSO
 
4.85
%
 
4.80
%
SWEPCo
 
4.80
%
 
4.80
%

(a)
Rates are for base pay only.  In addition, an amount is added to reflect target incentive compensation for exempt employees and overtime and incentive pay for nonexempt employees.
Benefit Obligations [Member] | Appalachian Power Co [Member]  
Actuarial Assumptions
 
 
Pension Plans
 
Other Postretirement
Benefit Plans
Assumption
 
2015
 
2014
 
2015
 
2014
Discount Rate
 
4.30
%
 
4.00
%
 
4.30
%
 
4.00
%
 
 
Pension Plans
Assumption – Rate of Compensation Increase (a)
 
2015
 
2014
AEP
 
4.80
%
 
4.80
%
APCo
 
4.45
%
 
4.45
%
I&M
 
4.75
%
 
4.80
%
OPCo
 
4.85
%
 
4.80
%
PSO
 
4.85
%
 
4.80
%
SWEPCo
 
4.80
%
 
4.80
%

(a)
Rates are for base pay only.  In addition, an amount is added to reflect target incentive compensation for exempt employees and overtime and incentive pay for nonexempt employees.
Benefit Obligations [Member] | Indiana Michigan Power Co [Member]  
Actuarial Assumptions
 
 
Pension Plans
 
Other Postretirement
Benefit Plans
Assumption
 
2015
 
2014
 
2015
 
2014
Discount Rate
 
4.30
%
 
4.00
%
 
4.30
%
 
4.00
%
 
 
Pension Plans
Assumption – Rate of Compensation Increase (a)
 
2015
 
2014
AEP
 
4.80
%
 
4.80
%
APCo
 
4.45
%
 
4.45
%
I&M
 
4.75
%
 
4.80
%
OPCo
 
4.85
%
 
4.80
%
PSO
 
4.85
%
 
4.80
%
SWEPCo
 
4.80
%
 
4.80
%

(a)
Rates are for base pay only.  In addition, an amount is added to reflect target incentive compensation for exempt employees and overtime and incentive pay for nonexempt employees.
Benefit Obligations [Member] | Ohio Power Co [Member]  
Actuarial Assumptions
 
 
Pension Plans
 
Other Postretirement
Benefit Plans
Assumption
 
2015
 
2014
 
2015
 
2014
Discount Rate
 
4.30
%
 
4.00
%
 
4.30
%
 
4.00
%
 
 
Pension Plans
Assumption – Rate of Compensation Increase (a)
 
2015
 
2014
AEP
 
4.80
%
 
4.80
%
APCo
 
4.45
%
 
4.45
%
I&M
 
4.75
%
 
4.80
%
OPCo
 
4.85
%
 
4.80
%
PSO
 
4.85
%
 
4.80
%
SWEPCo
 
4.80
%
 
4.80
%

(a)
Rates are for base pay only.  In addition, an amount is added to reflect target incentive compensation for exempt employees and overtime and incentive pay for nonexempt employees.
Benefit Obligations [Member] | Public Service Co Of Oklahoma [Member]  
Actuarial Assumptions
 
 
Pension Plans
 
Other Postretirement
Benefit Plans
Assumption
 
2015
 
2014
 
2015
 
2014
Discount Rate
 
4.30
%
 
4.00
%
 
4.30
%
 
4.00
%
 
 
Pension Plans
Assumption – Rate of Compensation Increase (a)
 
2015
 
2014
AEP
 
4.80
%
 
4.80
%
APCo
 
4.45
%
 
4.45
%
I&M
 
4.75
%
 
4.80
%
OPCo
 
4.85
%
 
4.80
%
PSO
 
4.85
%
 
4.80
%
SWEPCo
 
4.80
%
 
4.80
%

(a)
Rates are for base pay only.  In addition, an amount is added to reflect target incentive compensation for exempt employees and overtime and incentive pay for nonexempt employees.
Benefit Obligations [Member] | Southwestern Electric Power Co [Member]  
Actuarial Assumptions
 
 
Pension Plans
 
Other Postretirement
Benefit Plans
Assumption
 
2015
 
2014
 
2015
 
2014
Discount Rate
 
4.30
%
 
4.00
%
 
4.30
%
 
4.00
%
 
 
Pension Plans
Assumption – Rate of Compensation Increase (a)
 
2015
 
2014
AEP
 
4.80
%
 
4.80
%
APCo
 
4.45
%
 
4.45
%
I&M
 
4.75
%
 
4.80
%
OPCo
 
4.85
%
 
4.80
%
PSO
 
4.85
%
 
4.80
%
SWEPCo
 
4.80
%
 
4.80
%

(a)
Rates are for base pay only.  In addition, an amount is added to reflect target incentive compensation for exempt employees and overtime and incentive pay for nonexempt employees.
Benefit Costs [Member]  
Actuarial Assumptions
 
 
Pension Plans
 
Other Postretirement
Benefit Plans
Assumptions
 
2015
 
2014
 
2013
 
2015
 
2014
 
2013
Discount Rate
 
4.00
%
 
4.70
%
 
3.95
%
 
4.00
%
 
4.70
%
 
3.95
%
Expected Return on Plan Assets
 
6.00
%
 
6.00
%
 
6.50
%
 
6.75
%
 
6.75
%
 
7.00
%
 
 
Pension Plans
Assumption – Rate of Compensation Increase (a)
 
2015
 
2014
 
2013
AEP
 
4.80
%
 
4.85
%
 
4.95
%
APCo
 
4.45
%
 
4.60
%
 
4.70
%
I&M
 
4.80
%
 
4.90
%
 
5.00
%
OPCo
 
4.80
%
 
5.00
%
 
5.00
%
PSO
 
4.80
%
 
4.90
%
 
4.90
%
SWEPCo
 
4.80
%
 
4.85
%
 
4.75
%


(a)
Rates are for base pay only.  In addition, an amount is added to reflect target incentive compensation for exempt employees and overtime and incentive pay for nonexempt employees.
Benefit Costs [Member] | Appalachian Power Co [Member]  
Actuarial Assumptions
 
 
Pension Plans
 
Other Postretirement
Benefit Plans
Assumptions
 
2015
 
2014
 
2013
 
2015
 
2014
 
2013
Discount Rate
 
4.00
%
 
4.70
%
 
3.95
%
 
4.00
%
 
4.70
%
 
3.95
%
Expected Return on Plan Assets
 
6.00
%
 
6.00
%
 
6.50
%
 
6.75
%
 
6.75
%
 
7.00
%
 
 
Pension Plans
Assumption – Rate of Compensation Increase (a)
 
2015
 
2014
 
2013
AEP
 
4.80
%
 
4.85
%
 
4.95
%
APCo
 
4.45
%
 
4.60
%
 
4.70
%
I&M
 
4.80
%
 
4.90
%
 
5.00
%
OPCo
 
4.80
%
 
5.00
%
 
5.00
%
PSO
 
4.80
%
 
4.90
%
 
4.90
%
SWEPCo
 
4.80
%
 
4.85
%
 
4.75
%


(a)
Rates are for base pay only.  In addition, an amount is added to reflect target incentive compensation for exempt employees and overtime and incentive pay for nonexempt employees.
Benefit Costs [Member] | Indiana Michigan Power Co [Member]  
Actuarial Assumptions
 
 
Pension Plans
 
Other Postretirement
Benefit Plans
Assumptions
 
2015
 
2014
 
2013
 
2015
 
2014
 
2013
Discount Rate
 
4.00
%
 
4.70
%
 
3.95
%
 
4.00
%
 
4.70
%
 
3.95
%
Expected Return on Plan Assets
 
6.00
%
 
6.00
%
 
6.50
%
 
6.75
%
 
6.75
%
 
7.00
%
 
 
Pension Plans
Assumption – Rate of Compensation Increase (a)
 
2015
 
2014
 
2013
AEP
 
4.80
%
 
4.85
%
 
4.95
%
APCo
 
4.45
%
 
4.60
%
 
4.70
%
I&M
 
4.80
%
 
4.90
%
 
5.00
%
OPCo
 
4.80
%
 
5.00
%
 
5.00
%
PSO
 
4.80
%
 
4.90
%
 
4.90
%
SWEPCo
 
4.80
%
 
4.85
%
 
4.75
%


(a)
Rates are for base pay only.  In addition, an amount is added to reflect target incentive compensation for exempt employees and overtime and incentive pay for nonexempt employees.
Benefit Costs [Member] | Ohio Power Co [Member]  
Actuarial Assumptions
 
 
Pension Plans
 
Other Postretirement
Benefit Plans
Assumptions
 
2015
 
2014
 
2013
 
2015
 
2014
 
2013
Discount Rate
 
4.00
%
 
4.70
%
 
3.95
%
 
4.00
%
 
4.70
%
 
3.95
%
Expected Return on Plan Assets
 
6.00
%
 
6.00
%
 
6.50
%
 
6.75
%
 
6.75
%
 
7.00
%
 
 
Pension Plans
Assumption – Rate of Compensation Increase (a)
 
2015
 
2014
 
2013
AEP
 
4.80
%
 
4.85
%
 
4.95
%
APCo
 
4.45
%
 
4.60
%
 
4.70
%
I&M
 
4.80
%
 
4.90
%
 
5.00
%
OPCo
 
4.80
%
 
5.00
%
 
5.00
%
PSO
 
4.80
%
 
4.90
%
 
4.90
%
SWEPCo
 
4.80
%
 
4.85
%
 
4.75
%


(a)
Rates are for base pay only.  In addition, an amount is added to reflect target incentive compensation for exempt employees and overtime and incentive pay for nonexempt employees.
Benefit Costs [Member] | Public Service Co Of Oklahoma [Member]  
Actuarial Assumptions
 
 
Pension Plans
 
Other Postretirement
Benefit Plans
Assumptions
 
2015
 
2014
 
2013
 
2015
 
2014
 
2013
Discount Rate
 
4.00
%
 
4.70
%
 
3.95
%
 
4.00
%
 
4.70
%
 
3.95
%
Expected Return on Plan Assets
 
6.00
%
 
6.00
%
 
6.50
%
 
6.75
%
 
6.75
%
 
7.00
%
 
 
Pension Plans
Assumption – Rate of Compensation Increase (a)
 
2015
 
2014
 
2013
AEP
 
4.80
%
 
4.85
%
 
4.95
%
APCo
 
4.45
%
 
4.60
%
 
4.70
%
I&M
 
4.80
%
 
4.90
%
 
5.00
%
OPCo
 
4.80
%
 
5.00
%
 
5.00
%
PSO
 
4.80
%
 
4.90
%
 
4.90
%
SWEPCo
 
4.80
%
 
4.85
%
 
4.75
%


(a)
Rates are for base pay only.  In addition, an amount is added to reflect target incentive compensation for exempt employees and overtime and incentive pay for nonexempt employees.
Benefit Costs [Member] | Southwestern Electric Power Co [Member]  
Actuarial Assumptions
 
 
Pension Plans
 
Other Postretirement
Benefit Plans
Assumptions
 
2015
 
2014
 
2013
 
2015
 
2014
 
2013
Discount Rate
 
4.00
%
 
4.70
%
 
3.95
%
 
4.00
%
 
4.70
%
 
3.95
%
Expected Return on Plan Assets
 
6.00
%
 
6.00
%
 
6.50
%
 
6.75
%
 
6.75
%
 
7.00
%
 
 
Pension Plans
Assumption – Rate of Compensation Increase (a)
 
2015
 
2014
 
2013
AEP
 
4.80
%
 
4.85
%
 
4.95
%
APCo
 
4.45
%
 
4.60
%
 
4.70
%
I&M
 
4.80
%
 
4.90
%
 
5.00
%
OPCo
 
4.80
%
 
5.00
%
 
5.00
%
PSO
 
4.80
%
 
4.90
%
 
4.90
%
SWEPCo
 
4.80
%
 
4.85
%
 
4.75
%


(a)
Rates are for base pay only.  In addition, an amount is added to reflect target incentive compensation for exempt employees and overtime and incentive pay for nonexempt employees.