The Wisconsin Department of Public Instruction, headquartered in Madison, is the state education agency of Wisconsin. It is also the state agency concerned with public libraries in Wisconsin. The department is led by the State Superintendent of Public Instruction, a non-partisan, constitutional officer elected every four years. Tony Evers was elected state superintendent in 2009, and re-elected to another 4 year term in 2013. Supported by public tax levies and the free school movement, public school attendance in Wisconsin has increased from 14,000 students in 1846 to 870,470 students in the 2011-2012 school year.