The District of Columbia passed charter school legislation in 1996, which went into effect in September 1999. The legislation gave the District the power to grant charters for 15 years. Although this is longer than the traditional 3–5 year term observed in 31 other states, a required review takes place every 5 years. 4.4% of public school students enrolled in a charter school for the 1999 academic school year; the 28 schools had a total enrollment of approx. 3,000 students. After legislation was enacted in 2007, chartering authority was placed under the D.C. Public Charter School Board and disaffiliated from DCPS. The governance of DCPS was also restructured, and the district was placed under the control of the Mayor. In 2010 about 38% of Washington, D.C. public school students attended 60 charter schools. There are 52 public charter schools in the District, with 93 campuses and 30,000 students. The total number of public charter schools has been reduced from 60 schools on 96 campuses in 2008–09 to 53 schools on 98 campuses as of the 2011–12 school year. However, the addition of grades to the charter schools are still increasing enrollment and decreasing from DCPS’ numbers.