* Value statistically significantly different (p < .05) from 2010.
** Accommodations not permitted for English language learners and students with disabilities; such accommodations permitted in later years.
Source: U.S. Department of Education, Institute of Education Sciences, National Center for Education Statistics, National Assessment of Educational Progress, The Nation’s Report Card: U.S. History 2010, NCES 2011-468 (Washington, DC: U.S. Government Printing Office, 2011), 2 fig. C.