Benefit Plans

We have various pension and other defined benefit and defined contribution plans, in which substantially all employees may participate. We also have non-qualified supplemental executive and Board retirement plans.

Components of net periodic benefit costs for the three and nine months ended May 31, 2016, and 2015 are as follows:



	Qualified Pension Benefits						Non-Qualified Pension Benefits				Other Benefits
	2016			2015			2016		2015		2016			2015
Components of net periodic benefit costs for the three months ended May 31 are as follows:	(Dollars in thousands)
Service cost	$	9,383		$	8,889		$	258	$	206	$	353		$	188
Interest cost	7,691			7,003			352		357		427			288
Expected return on assets	(12,013		)	(12,431		)	—		—		—			—
Prior service cost (credit) amortization	402			407			57		57		(30		)	(30		)
Actuarial (gain) loss amortization	4,765			4,916			172		272		(116		)	(342		)
Net periodic benefit cost	$	10,228		$	8,784		$	839	$	892	$	634		$	104
Components of net periodic benefit costs for the nine months ended May 31 are as follows:
Service cost	$	28,149		$	27,005		$	776	$	656	$	1,059		$	1,134
Interest cost	23,075			21,019			1,055		1,061		1,282			1,118
Expected return on assets	(36,040		)	(37,305		)	—		—		—			—
Prior service cost (credit) amortization	1,205			1,223			171		171		(90		)	(90		)
Actuarial (gain) loss amortization	14,294			14,724			518		794		(348		)	(553		)
Net periodic benefit cost	$	30,683		$	26,666		$	2,520	$	2,682	$	1,903		$	1,609

Employer Contributions

Total contributions to be made during fiscal 2016, will depend primarily on market returns on the pension plan assets and minimum funding level requirements. During the nine months ended May 31, 2016, CHS made a voluntary contribution of $43.4 million to the pension plans. At this time, we do not anticipate having to make a required contribution for our benefit plans in fiscal 2016.