PENSION AND POSTRETIREMENT BENEFITS

We have defined benefit retirement plans ("plans") for eligible salaried and hourly employees. Benefits are based on years of credited service and average compensation or stated amounts for each year of service. We also sponsor postretirement plans which provide certain medical and dental benefits ("other postretirement benefits") to qualifying U.S. employees.

During the second quarter of fiscal 2018, we approved the amendment of our salaried and non-qualified pension plans effective as of December 31, 2017. The amendment will freeze the compensation and service periods used to calculate pension benefits for active employees who participate in the plans. Beginning January 1, 2018, impacted employees will not accrue additional benefit for future service and eligible compensation received under these plans.

As a result of the amendment, we were required to remeasure our pension plan liability as of September 30, 2017. In connection with the remeasurement, we updated the effective discount rate assumption from 3.90% to 3.78%. The curtailment and related remeasurement resulted in a net decrease to the underfunded status of the pension plans by $43.5 million with a corresponding benefit within other comprehensive income (loss) for the second quarter of fiscal 2018. In addition, we recorded charges of $3.4 million and $0.7 million reflecting the write-off of actuarial losses in excess of 10% of our pension liability and a curtailment charge, respectively.

Components of pension benefit and other postretirement benefit costs are (includes amounts related to discontinued operations):



	Pension Benefits
	Thirteen weeks ended						Twenty-six weeks ended
	November 26, 2017			November 27, 2016			November 26, 2017			November 27, 2016
Service cost	$	13.2		$	15.9		$	25.9		$	32.6
Interest cost	27.7			29.9			55.9			59.9
Expected return on plan assets	(54.6		)	(53.9		)	(108.8		)	(107.7		)
Amortization of prior service cost	0.7			0.7			1.4			1.3
Recognized net actuarial loss	3.4			—			3.4			—
Special termination benefits	—			1.5			—			1.5
Curtailment loss	0.7			—			0.7			—
Benefit cost (benefit) — Company plans	(8.9		)	(5.9		)	(21.5		)	(12.4		)
Pension benefit cost — multi-employer plans	4.2			2.8			5.7			5.1
Total benefit cost (benefit)	$	(4.7	)	$	(3.1	)	$	(15.8	)	$	(7.3	)



	Postretirement Benefits
	Thirteen weeks ended						Twenty-six weeks ended
	November 26, 2017			November 27, 2016			November 26, 2017			November 27, 2016
Service cost	$	—		$	0.1		$	—		$	0.1
Interest cost	0.9			1.0			1.8			2.1
Amortization of prior service benefit	(0.8		)	(1.6		)	(1.6		)	(3.3		)
Recognized net actuarial loss	—			0.1			—			0.2
Total cost (benefit)	$	0.1		$	(0.4	)	$	0.2		$	(0.9	)

The Company uses a split discount rate (spot-rate approach) for the U.S. plans and certain foreign plans. The spot-rate approach applies separate discount rates for each projected benefit payment in the calculation of pension service and interest cost.

The weighted-average discount rates for service and interest costs under the spot-rate approach used for pension benefit cost from May 29, 2017 through September 30, 2017, were 4.19% and 3.26%, respectively. The weighted-average discount rates for service and interest costs subsequent to September 30, 2017 are 4.04% and 3.24%, respectively.

During the second quarter and first half of fiscal 2018, we contributed $2.3 million and $6.1 million, respectively, to our pension plans and contributed $3.0 million and $6.9 million, respectively, to our other postretirement plans. Based upon the current funded status of the plans and the current interest rate environment, we anticipate making further contributions of approximately $6.8 million to our pension plans for the remainder of fiscal 2018. We anticipate making further contributions of approximately $11.8 million to our other postretirement plans during the remainder of fiscal 2018. These estimates are based on ERISA guidelines, current tax laws, plan asset performance, and liability assumptions, which are subject to change.

During the second quarter of fiscal 2018, we recorded an expense of $2.1 million related to our expected incurrence of certain multi-employer pension plan withdrawal costs. This expense has been included in restructuring activities.