4. POSTRETIREMENT BENEFITS

The Company provides pension benefits through a number of noncontributory and contributory defined benefit retirement plans covering eligible U.S. employees. As of September 30, 2017, all defined pension benefit plans were frozen, whereby participants no longer accrue credited service. The net periodic benefit cost was as follows:



		Three months ended						Six months ended
(in thousands)	Note	March 30, 2018			March 31, 2017			March 30, 2018			March 31, 2017
Service cost		$	—		$	512		$	—		$	1,024
Interest cost	6	1,025			948			2,049			1,897
Expected return on plan assets	6	(1,604		)	(1,650		)	(3,207		)	(3,300		)
Amortization of actuarial loss	6	86			326			171			651
Net periodic benefit cost		$	(493	)	$	136		$	(987	)	$	272

During fiscal 2018, the Company adopted ASU 2017-07 Compensation - Retirement Benefits (Topic 715): Improving the Presentation of Net Periodic Pension Cost and Net Periodic Postretirement Benefit Cost. As a result, service costs are included as a component of cost of sales and selling, general and administrative expenses on the Company's condensed consolidated statements of operations. All other components of net periodic benefit costs are included as a component of other income, net on the Company's condensed consolidated statements of operations. Certain prior year amounts have been reclassified to conform to the current year presentation in our condensed consolidated financial statements. Prior to the adoption of ASU 2017-07, pension costs were reported as cost of sales and selling, general and administrative expenses on the Company's condensed consolidated statements of income. As a result of the early adoption of ASU 2017-07, the Company reclassified $376 and $752 from operating income to other income, net on the condensed consolidated statements of operations for the three and six months ended March 31, 2017, respectively.