The Center on Budget and Policy Priorities has released A Hand Up:  How State Earned Income Tax Credits Help Working Families Escape Poverty In 2006, by Ami Nagle & Nicholas Johnson:

An Earned Income Tax Credit is a tax reduction and a wage supplement for low- and moderate-income working families. The federal government administers an EITC through the income tax. So do many states. States that enact EITCs can reduce child poverty, increase effective wages, and cut taxes for families struggling to make ends meet.

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