EMPLOYEE BENEFITS

The following tables show the components of net periodic pension and OPEB costs for our benefit plans.



	Pension Costs
	Three Months Ended September 30						Nine Months Ended September 30
(in millions)	2017			2016			2017			2016
Service cost	$	11.1		$	10.9		$	33.2		$	32.9
Interest cost	30.3			33.2			91.7			99.4
Expected return on plan assets	(48.8		)	(49.0		)	(146.9		)	(147.0		)
Loss on plan settlement	2.9			0.7			8.2			14.8
Amortization of prior service cost	0.7			0.9			2.2			2.6
Amortization of net actuarial loss	21.5			20.4			64.5			61.1
Net periodic benefit cost	$	17.7		$	17.1		$	52.9		$	63.8



	OPEB Costs
	Three Months Ended September 30						Nine Months Ended September 30
(in millions)	2017			2016			2017			2016
Service cost	$	6.0		$	6.5		$	17.9		$	19.6
Interest cost	8.4			9.2			25.3			27.7
Expected return on plan assets	(13.6		)	(13.2		)	(40.9		)	(39.6		)
Amortization of prior service credit	(2.8		)	(2.3		)	(8.4		)	(7.0		)
Amortization of net actuarial loss	0.7			2.2			2.3			6.4
Net periodic benefit (credit) cost	$	(1.3	)	$	2.4		$	(3.8	)	$	7.1

During the nine months ended September 30, 2017, we made payments of $109.8 million to our pension plans and $5.6 million to our OPEB plans. We expect to make payments of $3.8 million related to our pension plans and $3.9 million related to our OPEB plans during the remainder of 2017, dependent upon various factors affecting us, including our liquidity position and possible tax law changes.