| Figure 10. | Percentage of revenue for public elementary and secondary schools, by source of funds: 1970-71 through 2011-12 |
| SOURCE: U.S. Department of Education, National Center for Education Statistics, Revenues and Expenditures for Public Elementary and Secondary Education, 1970-71 through 1986-87; and Common Core of Data (CCD), "National Public Education Financial Survey," 1987-88 through 2011-12. |