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NAEP Technical DocumentationAge Distribution Fractions for Age 17

The derivation of the age distribution factors was much more straightforward than for the age 9 and 13 components. Estimates from the October 2005 Current Population Survey (CPS) School Supplement were utilized to provide the percentages of sixteen-year-olds within each of ninth, tenth, eleventh, and twelfth grades by Census region. Sixteen-year-olds were used because this age definition is based on an October-September birth cohort. The age distribution fractions are identical for public and private schools since the CPS does not provide grade enrollment data by school type.

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