The 2006–07 school year EDFacts collection of CCD data opened on January 16, 2007 and closed on April 30, 2008.
NCES imputes (replaces a nonresponse with a plausible value) some missing items in the State Nonfiscal Survey of Public Elementary/Secondary Education Survey, but does not impute missing items in the Public Elementary/ Secondary School Universe Survey or the Local Education Agency Universe Survey.
When reporting results, NCES treats missing data within individual states differently than it treats missing data across all states and the District of Columbia. An individual state is considered to have missing data if an item is reported for less than 80 percent of possible cases.
If information is missing for some but no more than 15 percent of possible cases across the 50 states and District of Columbia, NCES calculates totals and identifies them as "reporting states" totals (rather than totals for the United States). None of states or the District of Columbia had missing data for any of the data items used in this report. Precise information about missing data is included in the documentation for the Local Education Agency Universe Survey 2006–07 file.
EDFacts accepted blank responses in 2006–07 school year reports and did not require that states distinguish among missing, not applicable, and "zero" values. Every effort was made to correctly identify responses as missing, not applicable, or zero after the fact, but it is possible that some blank responses were categorized incorrectly.
Some operational schools or agencies may legitimately not report students. The CCD allows a student to be reported for only a single school or agency. A vocational school or a local education agency operating only vocational schools may provide classes for students from a number of regular schools or school districts. In this case, the students are usually reported in the membership of their school of record, and the vocational school (identified as a "shared time" school) shows no student membership.