Interim Pension and Other Postretirement Benefit Plan Information

The components of our net periodic pension cost for our pension and other postretirement benefit plans for the three and nine months ended June 30, 2018 and 2017 are presented in the following tables. Most of these costs are recoverable through our tariff rates. A portion of these costs is capitalized into our rate base. The remaining costs are recorded as a component of operation and maintenance expense.

In the second quarter of fiscal 2018, due to the retirement of certain executives, we recognized a settlement loss of $2.4 million associated with our Supplemental Executive Retirement Plan and revalued the net periodic pension cost for the remainder of fiscal 2018. The revaluation of the net periodic pension cost for our Supplemental Executive Retirement Plan resulted in an increase in the discount rate, effective March 1, 2018, to 4.12% from 3.89%, which will increase our net periodic pension cost by approximately $0.1 million for the remainder of the fiscal year.

In the third quarter of fiscal 2018, due to the retirement of one of our executives, we recognized a settlement loss of $0.9 million associated with our Supplemental Executive Retirement Plan and revalued the net periodic pension cost for the remainder of fiscal 2018. The revaluation of the net periodic pension cost for our Supplemental Executive Retirement Plan resulted in an increase in the discount rate, effective June 5, 2018, to 4.29% from 4.12%, which will increase our net periodic pension cost by approximately $0.2 million for the remainder of the fiscal year.



	Three Months Ended June 30
	Pension Benefits						Other Benefits
	2018			2017			2018			2017
	(In thousands)
Components of net periodic pension cost:
Service cost	$	4,794		$	5,216		$	3,020		$	3,109
Interest cost	6,448			6,296			2,726			2,669
Expected return on assets	(6,917		)	(6,993		)	(2,002		)	(1,796		)
Amortization of prior service cost (credit)	(57		)	(57		)	2			(411		)
Amortization of actuarial (gain) loss	3,050			4,248			(1,618		)	(706		)
Settlements	888			—			—			—
Net periodic pension cost	$	8,206		$	8,710		$	2,128		$	2,865



	Nine Months Ended June 30
	Pension Benefits						Other Benefits
	2018			2017			2018			2017
	(In thousands)
Components of net periodic pension cost:
Service cost	$	13,929		$	15,649		$	9,059		$	9,327
Interest cost	19,311			18,890			8,180			8,009
Expected return on assets	(20,750		)	(20,981		)	(6,005		)	(5,389		)
Amortization of prior service cost (credit)	(173		)	(173		)	8			(1,233		)
Amortization of actuarial (gain) loss	9,224			12,746			(4,855		)	(2,120		)
Settlements	3,303			—			—			—
Net periodic pension cost	$	24,844		$	26,131		$	6,387		$	8,594

The assumptions used to develop our net periodic pension cost for the three and nine months ended June 30, 2018 and 2017 are as follows:



	Supplemental Executive Retirement Plan		Pension Benefits		Other Benefits
	2018	2017	2018	2017	2018	2017
Discount rate	4.29%	3.73%	3.89%	3.73%	3.89%	3.73%
Rate of compensation increase	3.50%	3.50%	3.50%	3.50%	N/A	N/A
Expected return on plan assets	N/A	N/A	6.75%	7.00%	4.29%	4.45%

The discount rate used to compute the present value of a plan’s liabilities generally is based on rates of high-grade corporate bonds with maturities similar to the average period over which the benefits will be paid. Generally, our funding policy has been to contribute annually an amount in accordance with the requirements of the Employee Retirement Income Security Act of 1974. In accordance with the Pension Protection Act of 2006 (PPA), we determined the funded status of our plan as of January 1, 2018. Based on that determination, we are not required to make a minimum contribution to our defined benefit plan during fiscal 2018; however, we may consider whether a voluntary contribution is prudent to maintain certain funding levels.

We contributed $11.4 million to our other post-retirement benefit plans during the nine months ended June 30, 2018. We expect to contribute a total of between $10 million and $20 million to these plans during fiscal 2018.