8. EMPLOYEE BENEFITS

Pension Plan

We maintain a Pension Plan, which covers certain eligible employees and retirees and has been frozen since March 31, 2009. No new participants may enter the Pension Plan and no further benefits will accrue. However, years of service continue to count toward early retirement calculations and vesting of benefits previously earned.

We also have a limited number of supplemental retirement plans to provide certain key employees and retirees with additional retirement benefits. These plans are funded on a pay-as-you-go basis and the accrued pension obligation is largely included in pension and postretirement obligations.

Effective with the filing of our Chapter 11 Cases, we have reclassified the current and long-term portions of the pension and supplemental retirement plan liabilities from accrued pension liabilities and pension and post-retirement obligations, respectively, to liabilities subject to compromise on the March 29, 2020, condensed consolidated balance sheet. The obligations related to our post-retirement health and welfare plan were not moved to liabilities subject to compromise because that plan was approved by the Bankruptcy Court in the Chapter 11 Cases proceedings. See Note 2 for details of the liabilities subject to compromise.

The elements of retirement benefit expense are as follows:


	Three Months Ended
	March 29,		March 31,
(in thousands)	2020		2019
Pension plans:
Interest Cost	$	17,302	$	20,521
Expected return on plan assets		(20,209)		(21,502)
Special termination benefits		—		6,834
Actuarial loss		7,239		5,525
Net pension expense		4,332		11,378
Net post-retirement benefit credit		(465)		(651)
Net retirement benefit expenses	$	3,867	$	10,727

Early Retirement Incentive Program

In February 2019, we announced a one-time voluntary Early Retirement Incentive Program (“ERIP”) that was offered to approximately 450 employees. The ERIP allowed the employees to accept a special termination benefit based on years of continuous service and the option to take their vested benefits under our frozen Pension Plan in a lump sum payment. Nearly 50% of the eligible employees opted into the program.

Lump sum pension and termination payments made under the ERIP totaled approximately $35.1 million, decreasing both the benefit obligation and the fair value of plan assets. Due to the significance of this program, we remeasured the retirement plan assets and benefit obligations as of March 22, 2019. The remeasurement and the special termination benefits resulted in a net reduction to the pension liability and the recognition of a one-time non-cash charge of $6.8 million for the special termination benefits, presented in retirement benefit expense on the condensed consolidated statement of operations during the three months ended March 31, 2019.

401(k) Plan

We have a deferred compensation plan (“401(k) plan”), which enables eligible employees to defer compensation. In the three months ended March 29, 2020, and March 31, 2019, our matching contributions were $0.5 million and $0.6 million, respectively. Matching contributions are recorded in the compensation line item of our condensed consolidated statement of operations.