Borrowings and Lines of Credit



(Dollars in millions)	September 30, 2017		December 31, 2016
Commercial paper	$	943	$	522
Other borrowings	134		79
Total short-term borrowings	$	1,077	$	601

At September 30, 2017, we had revolving credit agreements with various banks permitting aggregate borrowings of up to $4.35 billion, pursuant to a $2.20 billion revolving credit agreement and a $2.15 billion multicurrency revolving credit agreement, both of which expire in August 2021. As of September 30, 2017, there were no borrowings under these revolving credit agreements. The undrawn portions of these revolving credit agreements are also available to serve as backup facilities for the issuance of commercial paper. As of September 30, 2017, our maximum commercial paper borrowing limit was $4.35 billion. Commercial paper borrowings at September 30, 2017 include approximately €500 million ($594 million) of euro-denominated commercial paper. We use our commercial paper borrowings for general corporate purposes, including the funding of potential acquisitions, discretionary pension contributions, debt refinancing, dividend payments and repurchases of our common stock. The need for commercial paper borrowings arises when the use of domestic cash for general corporate purposes exceeds the sum of domestic cash generation and foreign cash repatriated to the U.S.

In connection with the merger agreement with Rockwell Collins announced on September 4, 2017, we have entered into a $6.5 billion 364-day unsecured bridge loan credit agreement that would be funded only to the extent certain anticipated debt issuances are not completed prior to the completion of the merger. See Note 1 for additional discussion.

On May 4, 2017, we issued $1.0 billion aggregate principal amount of 1.900% notes due 2020, $500 million aggregate principal amount of 2.300% notes due 2022, $800 million aggregate principal amount of 2.800% notes due 2024, $1.1 billion aggregate principal amount of 3.125% notes due 2027 and $600 million aggregate principal amount of 4.050% notes due 2047. The net proceeds received from these debt issuances were used to fund the repayment at maturity of our 1.800% notes due 2017, representing $1.5 billion in aggregate principal, and for other general corporate purposes.

Long-term debt consisted of the following:



(Dollars in millions)	September 30, 2017			December 31, 2016
1.800% notes due 2017 ¹	$	—		$	1,500
6.800% notes due 2018	99			99
EURIBOR plus 0.800% floating rate notes due 2018 (€750 million principal value) ²	890			783
1.778% junior subordinated notes due 2018	1,100			1,100
LIBOR plus 0.350% floating rate notes due 2019 ³	350			350
1.500% notes due 2019 ¹	650			650
8.875% notes due 2019	271			271
4.875% notes due 2020 ¹	171			171
4.500% notes due 2020 ¹	1,250			1,250
1.900% notes due 2020 ¹	1,000			—
8.750% notes due 2021	250			250
1.950% notes due 2021 ¹	750			750
1.125% notes due 2021 (€950 million principal value) ¹	1,128			992
2.300% notes due 2022 ¹	500			—
3.100% notes due 2022 ¹	2,300			2,300
1.250% notes due 2023 (€750 million principal value) ¹	890			783
2.800% notes due 2024 ¹	800			—
1.875% notes due 2026 (€500 million principal value) ¹	594			522
2.650% notes due 2026 ¹	1,150			1,150
3.125% notes due 2027 ¹	1,100			—
7.100% notes due 2027	141			141
6.700% notes due 2028	400			400
7.500% notes due 2029 ¹	550			550
5.400% notes due 2035 ¹	600			600
6.050% notes due 2036 ¹	600			600
6.800% notes due 2036 ¹	134			134
7.000% notes due 2038	159			159
6.125% notes due 2038 ¹	1,000			1,000
5.700% notes due 2040 ¹	1,000			1,000
4.500% notes due 2042 ¹	3,500			3,500
4.150% notes due 2045 ¹	850			850
3.750% notes due 2046 ¹	1,100			1,100
4.050% notes due 2047 ¹	600			—
Project financing obligations	137			155
Other (including capitalized leases)	195			189
Total principal long-term debt	26,209			23,299
Other (fair market value adjustments and discounts)	(26		)	1
Total long-term debt	26,183			23,300
Less: current portion	2,120			1,603
Long-term debt, net of current portion	$	24,063		$	21,697


1	We may redeem these notes at our option pursuant to their terms.


2	The three-month EURIBOR rate as of September 30, 2017 was approximately -0.329%. The notes may be redeemed at our option in whole, but not in part, at any time in the event of certain developments affecting U.S. taxation.


3	The three-month LIBOR rate as of September 30, 2017 was approximately 1.334%.

The average maturity of our long-term debt at September 30, 2017 is approximately twelve years. The average interest expense rate on our total borrowings for the quarters and nine months ended September 30, 2017 and 2016 was as follows:



	Quarter Ended September 30,				Nine Months Ended September 30,
	2017		2016		2017		2016
Average interest expense rate	3.6	%	4.0	%	3.6	%	4.1	%

We have an existing universal shelf registration statement filed with the Securities and Exchange Commission (SEC) for an indeterminate amount of equity and debt securities for future issuance, subject to our internal limitations on the amount of equity and debt to be issued under this shelf registration statement.