Charles Bruner and Andrew Cannon, Iowa Fiscal Partnership, March 2012. The Iowa Senate unanimously passed legislation to raise the state EITC to 13 percent of the federal credit for the 2012 tax year, going to 15 percent for 2013 and 20 percent for 2014. This would make Iowa’s EITC more in line with Iowa’s overall state income tax collections, which are about 30 percent the size of the federal income tax.