A reconciliation of the statutory federal income tax rate to our effective rate for continuing operations is provided below:

	Three Months Ended March 31,
	2020			2019
Statutory federal income tax rate		21.0	%		21.0	%
State income taxes, net of federal income tax		2.2			4.2
Stock compensation windfall benefit		(16.0	)		(0.1	)
Permanent differences and other		(4.4	)		(1.1	)
		2.8	%		24.0	%

On March 27, 2020, President Trump signed the Coronavirus Aid, Relief, and Economic Security Act ("CARES Act") into law. The CARES Act is a relief package intended to assist many aspects of the American economy disrupted by the COVID-19 pandemic. We are currently evaluating the impact of the CARES Act on our consolidated financial statements.

We base our estimate of deferred tax assets and liabilities on current tax laws and rates. In certain cases, we also base our estimate on business plan forecasts and other expectations about future outcomes. Changes in existing tax laws or rates could affect our actual tax results, and future business results may affect the amount of our deferred tax liabilities or the valuation of our deferred tax assets over time. Due to uncertainties in the estimation process, particularly with respect to changes in facts and circumstances in future reporting periods, as well as the residential homebuilding industry’s cyclicality and sensitivity to changes in economic conditions, particularly due to economic disruptions related to the COVID-19 pandemic, it is possible that actual results could differ from the estimates used in previous analyses.

Accounting for deferred taxes is based upon estimates of future results. Differences between the anticipated and actual outcomes of these future results could have a material impact on our consolidated results of operations or financial position.