PENSION AND OTHER POSTRETIREMENT BENEFIT PLANS

The following table summarizes the components of net periodic pension cost and the cost of other postretirement benefits for the periods presented:



	Three Months Ended March 31,
	United States Pension Benefits						Foreign Pension Benefits						Other Postretirement Benefits
Millions of dollars	2019			2018			2019			2018			2019			2018
Service cost	$	1		$	1		$	1		$	1		$	2		$	2
Interest cost	31			30			6			6			4			4
Expected return on plan assets	(44		)	(43		)	(7		)	(8		)	—			—
Amortization:
Actuarial loss	12			13			2			3			—			—
Prior service cost (credit)	(1		)	(1		)	—			—			(2		)	3
Settlement and curtailment (gain) loss	—			—			1			—			(7		)	—
Net periodic benefit cost (credit)	$	(1	)	$	—		$	3		$	2		$	(3	)	$	9

The following table summarizes the net periodic cost recognized in operating profit and interest and sundry (income) expense for the periods presented:



	Three Months Ended March 31,
	United States Pension Benefits						Foreign Pension Benefits				Other Postretirement Benefits
Millions of dollars	2019			2018			2019		2018		2019			2018
Operating profit (loss)	$	1		$	1		$	1	$	1	$	2		$	2
Interest and sundry (income) expense	(2		)	(1		)	2		1		(5		)	7
Net periodic benefit cost	$	(1	)	$	—		$	3	$	2	$	(3	)	$	9

During the second quarter 2011, we modified retiree medical benefits for certain retirees to be consistent with those benefits provided by the Whirlpool Corporation Group Benefit Plan. We accounted for these changes as a plan amendment in 2011, resulting in a reduction in the postretirement benefit obligation of $138 million, of which approximately $89 million of benefit has been recognized in net earnings since 2011, with an offset to accumulated other comprehensive loss, net of tax. In response, a group of retirees initiated legal proceedings against Whirlpool asserting the above benefits are vested and changes to the plan are not permitted.

On February 15, 2019, we received a favorable decision from the United States Court of Appeals for the Sixth Circuit, which held that the benefits at issue are not vested for life and may be altered. Plaintiffs could seek further review of the Court's decision. On April 4, 2019, the Sixth Circuit Court issued a mandate to the district court, requiring it to take steps to implement this decision. The amount incurred in the first quarter of 2019 related to this decision was not material and we do not expect a material financial impact in future periods.