We have invested $188.0 million through our gas reserves program in the Jonah Field located in Wyoming as of March 31, 2018. Gas reserves are stated at cost, net of regulatory amortization, with the associated deferred tax benefits recorded as liabilities in the consolidated balance sheets. Our investment in gas reserves provides long-term price protection for utility customers through the original agreement with Encana Oil & Gas (USA) Inc. under which we invested $178.0 million and the amended agreement with Jonah Energy LLC under which an approximate additional $10 million was invested.

The cost of gas, including a carrying cost for the rate base investment, is included in our annual Oregon PGA filing, which allows us to recover these costs through customer rates. Our investment under the original agreement, less accumulated amortization and deferred taxes, earns a rate of return.

Gas produced from the additional wells is included in our Oregon PGA at a fixed rate of $0.4725 per therm, which approximates the 10-year hedge rate plus financing costs at the inception of the investment.

The following table outlines our net gas reserves investment:



	March 31,				December 31,
In thousands	2018		2017		2017
Gas reserves, current	$	15,124	$	15,378	$	15,704
Gas reserves, non-current	172,412		172,158		171,832
Less: Accumulated amortization	91,852		75,528		87,779
Total gas reserves⁽¹⁾	95,684		112,008		99,757
Less: Deferred taxes on gas reserves	22,115		32,179		22,712
Net investment in gas reserves	$	73,569	$	79,829	$	77,045


⁽¹⁾	Our net investment in additional wells included in total gas reserves was $5.6 million, $6.5 million and $5.8 million at March 31, 2018 and 2017 and December 31, 2017, respectively.

Our investment is included in our consolidated balance sheets under gas reserves with our maximum loss exposure limited to our investment balance.