Regulatory Assets and Liabilities

Regulatory assets and liabilities were comprised of the following as of June 30, 2018 and December 31, 2017:



	June 30, 2018		December 31, 2017
Regulatory Assets
Pension and retiree group health	$	213,920	$	214,249
Property-related temporary differences (tax benefits flowed through to customers)	87,988		87,323
Other accrued benefits	28,741		28,251
Net WRAM and MCBA long-term accounts receivable	32,892		34,879
Asset retirement obligations, net	17,824		17,126
Interim rates long-term accounts receivable	4,568		4,568
Tank coating	11,467		10,998
Health care balancing account	442		496
Pension balancing account	5,136		2,322
Other components of net periodic benefit cost	1,754		—
Other regulatory assets	565		935
Total Regulatory Assets	$	405,297	$	401,147

Regulatory Liabilities
Future tax benefits due to customers	$	168,384	$	168,343
Health care balancing account	11,127		7,749
Conservation program	4,531		2,273
Pension balancing account	13		364
Net WRAM and MCBA long-term payable	938		513
Tax accounting memorandum account	4,767		—
Cost of capital memorandum account	2,834		—
Other regulatory liabilities	161		464
Total Regulatory Liabilities	$	192,755	$	179,706

Short-term regulatory assets and liabilities are excluded from the above table.

The short-term regulatory assets were $33.3 million as of June 30, 2018 and $36.8 million as of December 31, 2017. As of June 30, 2018 and December 31, 2017, the short-term regulatory assets primarily consist of net WRAM and MCBA receivables.

The short-term portions of regulatory liabilities were $56.3 million as of June 30, 2018 and $59.3 million as of December 31, 2017. The short-term regulatory liabilities as of June 30, 2018, primarily consist of 1,2,3 trichloropropane (TCP) settlement proceeds. As of December 31, 2017, the short-term regulatory liabilities primarily consist of TCP settlement proceeds and net WRAM and MCBA liability balances.

The tax accounting and cost of capital memorandum account regulatory liabilities are related to the estimated customer refunds due to changes in the federal income tax rate and to the cost of capital decision for Cal Water.

The other components of net periodic benefit cost regulatory asset are authorized by the Commissions and are probable for rate recovery through the capital program (see Note 2).