 The Act 1 of 2006 Index regulates the rates at which each school district can raise property taxes in Pennsylvania.Districts are not authorized to raise taxes above that index unless they allow voters to vote by referendum, or the school board seeks one or more exceptions from the state's Department of Education.The base index for the 2011-2012 school year is 1.4 percent, but the Act 1 Index can be adjusted higher, depending on a number of factors, such as property values and the personal income of district residents.