Higher percentages of fourth-graders who attend public and Catholic schools performed at or above Basic in 2011 than in 1990, but differences in comparison to 2009 were not statistically significant.
A higher percentage of fourth-graders who attend public schools performed at or above Proficient in 2011 than in any of the previous assessment years.
Sample sizes were insufficient to permit reliable estimates for Bureau of Indian Education students in 1992–2003, Department of Defense students in 1992–2000, and other private school students in 2005-2011.