We had the following regulatory assets and liabilities (in millions):


	As of			As of
	March 31, 2024			December 31, 2023
Regulatory assets
Winter Storm Uri	$	144.9		$	199.6
Deferred energy and fuel cost adjustments		57.5			55.1
Deferred gas cost adjustments		8.1			4.1
Gas price derivatives		-			5.1
Deferred taxes on AFUDC		7.4			7.1
Employee benefit plans and related deferred taxes		88.2			89.3
Environmental		5.9			2.9
Loss on reacquired debt		17.0			17.4
Deferred taxes on flow through accounting		80.5			74.7
Decommissioning costs		2.4			2.4
Other regulatory assets		19.2			22.4
Total regulatory assets		431.1			480.1
Less current regulatory assets		(147.3	)		(175.7	)
Regulatory assets, non-current	$	283.8		$	304.4

Regulatory liabilities
Deferred energy and gas costs	$	85.7		$	88.9
Employee benefit plan costs and related deferred taxes		35.7			36.2
Cost of removal		182.2			181.9
Excess deferred income taxes		243.2			247.1
Other regulatory liabilities		6.6			12.5
Total regulatory liabilities		553.4			566.6
Less current regulatory liabilities		(89.9	)		(98.9	)
Regulatory liabilities, non-current	$	463.5		$	467.7

On December 4, 2023, Arkansas Gas filed a rate review with the APSC seeking recovery of significant infrastructure investments in its 7,200-mile natural gas pipeline system. The rate review requests $44.1 million in new annual revenue with a capital structure of 48% equity and 52% debt and a return on equity of 10.5%. The request seeks to finalize rates in the fourth quarter of 2024.

On May 9, 2023, Colorado Gas filed a rate review with the CPUC seeking recovery of significant infrastructure investments in its 10,000-mile natural gas pipeline system. In March 2024, Colorado Gas received final approval for a settlement agreement for a general rate increase which is expected to generate $20.2 million of new annual revenue with a capital structure of 51% equity and 49% debt and a return on equity of 9.3%. Final rates were enacted on May 1, 2024, and replaced interim rates effective February 13, 2024.

On May 1, 2024, Iowa Gas filed a rate review with the IUB seeking recovery of significant infrastructure investments in its 5,000-mile natural gas pipeline system. The rate review requests $20.7 million in new annual revenue with a capital structure of 51% equity and 49% debt and a return on equity of 10.5%. Iowa statute allows implementation of interim rates 10 days after filing a rate review and Iowa Gas plans to implement interim rates, subject to adjustment or refund, effective in May, 2024. The request seeks to finalize rates in the first quarter of 2025.

On May 18, 2023, Wyoming Gas filed a rate review with the WPSC seeking recovery of significant infrastructure investments in its 6,400-mile natural gas pipeline system. On January 17, 2024, the WPSC approved a settlement agreement for a general rate increase which is expected to generate $13.9 million in new annual revenue with a capital structure of 51% equity and 49% debt and a return on equity of 9.9%. New rates were effective February 1, 2024. The agreement also included approval of a four-year extension of the Wyoming Integrity Rider.