The estimation procedure employed for the monthly CPS data involves inflating weighted sample results to independent estimates for the total civilian noninstitutional population by age, sex, race, and Hispanic origin. Generalized standard error tables are provided in the Current Population Reports. The data are subject to both nonsampling and sampling errors. Each October, the CPS includes supplemental questions on the enrollment status of the population aged 3 and older. Annual reports documenting school enrollment of the population have been produced by the Bureau of the Census since 1946.
All sample surveys are subject to sampling and nonsampling error.
The main sources of nonsampling error in the supplement are those inherent in any household survey. Household reported data may not be consistent with administrative data because definitions may not be the same. An additional source of variation in statistics reported may be a change in the survey universe over time. For example, a significantly larger proportion of young men were members of the Armed Forces in the late 1960s and early 1970s than before or after and, therefore, were not in the CPS universe. That caused a short-term increase in the school enrollment rate of young men, which was greater than the increase in numbers of enrollees would indicate.