Benefit Plans

The components of net periodic cost for the Company’s pension and postretirement benefit plans are as follows:



($ in millions)	Three months ended September 30,						Nine months ended September 30,
	2017			2016			2017			2016
Pension benefits
Service cost	$	28		$	28		$	85		$	84
Interest cost	66			71			198			214
Expected return on plan assets	(102		)	(99		)	(306		)	(298		)
Amortization of:
Prior service credit	(14		)	(14		)	(42		)	(42		)
Net actuarial loss	48			44			142			131
Settlement loss	94			7			110			23
Net periodic pension cost	$	120		$	37		$	187		$	112

Postretirement benefits
Service cost	$	2		$	2		$	6		$	7
Interest cost	4			4			11			13
Amortization of:
Prior service credit	(6		)	(5		)	(18		)	(16		)
Net actuarial gain	(6		)	(2		)	(18		)	(18		)
Net periodic postretirement credit	$	(6	)	$	(1	)	$	(19	)	$	(14	)

During the third quarter of 2017, the Company concluded that its qualified employee pension plan 2017 lump sum payments are expected to exceed a threshold of service and interest cost due to higher-than-expected retirement levels, rising interest rates that reduce benefit lump sum payments in the future and reductions in force. As a result, a pension settlement loss of $86 million, pre-tax, was recorded as part of operating costs and expenses in the Corporate and Other segment. The Company will continue to monitor lump sum payments through the end of the year and will recognize an additional settlement expense based on lump sum payments made during the fourth quarter of 2017.