Notes
1. National Center for Educational Statistics, US Department of Education, Digest of Education Statistics: 2009, NCES 2010-013, April 2010, Table 26. Washington, DC: US Government Printing Office.
2. National Center for Educational Statistics, US Department of Education, Digest of Education Statistics: 2009, NCES 2010-013, April 2010, Table 27. Washington, DC: US Government Printing Office.