Deferred income taxes result from temporary differences in the recognition of income and expense for financial and income tax reporting purposes, and differences between the fair value of assets acquired in business combinations accounted for as purchases for financial reporting purposes and their corresponding tax bases. Deferred income taxes represent future tax benefits or costs to be recognized when those temporary differences reverse. The categories of assets and liabilities that have resulted in differences in the timing of the recognition of income and expense at December 31, 2021 and 2020 were as follows:


(In millions)	2021		2020
Deferred income tax assets
Net operating loss tax carryovers	$	298.7	$	309.4
Pensions	94.3		153.8
Postretirement benefits other than pensions	69.8		86.5
Tax credits	40.2		37.7
Other items	103.9		82.9
Gross deferred income tax assets	606.9		670.3
Valuation allowance for deferred tax assets	(431.0)		(461.8)
Total deferred income tax assets	175.9		208.5
Deferred income tax liabilities
Bases of property, plant and equipment	114.0		119.2
Inventory valuation	32.5		53.3
Bases of amortizable intangible assets	18.0		12.5
Other items	24.7		35.9
Total deferred tax liabilities	189.2		220.9
Net deferred tax liability	$	(13.3)	$	(12.4)

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