School, dropout rate, annual high school.
        The annual high school dropout rate is an estimate of the proportion of students who drop out of school in a single year. This section briefly explains how the annual dropout rate is calculated; for further explanation and details of its derivation see Current Population Report, Series P-20, No. 413, "School Enrollment--Social and Economic Characteristics of Students: October 1983."

        Annual dropout rates for a single grade (x) are estimated as the ratio of the number of people who were enrolled in grade (x) in the year preceding the survey and who did not complete grade (x) and are not currently enrolled, to the number enrolled in grade (x) at the start of the year preceding this survey. People reported as enrolled last year but not currently enrolled are presented in table 8 of Current Population Reports on school enrollment, by the highest grade completed and are presumed to have dropped out of the succeeding grade (except those who graduated this year). Thus, individuals counted as 10th grade dropouts are those not enrolled in school whose highest grade completed is the 9th grade. (They include not only those people who were enrolled in the 10th grade in the fall of the year preceding the survey and left school without completing the year, but also those people who finished the 9th grade in the spring preceding the survey and were not enrolled at the survey date.) These estimates form the numerator of estimates of the annual grade specific dropout rate.

People currently enrolled in high school are presumed to have successfully completed and been enrolled in the preceding grade in the preceding year. Thus, those who have successfully completed the 10th grade are enrolled in the 11th grade. Along with the people who dropped out of that grade, they comprise the denominator of the estimate of the annual grade-specific dropout rate.
grade n
Not enrolled and highest grade completed = n-1
= Enrolled in
    grade n+1
Not enrolled and highest
+grade completed = n-1

        Since people who complete the 12th grade cannot be presumed to enroll in college, the estimate of the number of people enrolled in the 12th grade one year prior to the survey is constructed as the sum of the number of people reported as having graduated from high school "this year" (both those enrolled in the first year of college and people not currently enrolled whose highest grade completed is the 12th grade) and those people not currently enrolled who were enrolled last year and whose highest grade completed is the 11th grade (dropouts). The annual dropout rate for all grades during one year can be obtained by summing the components of the rates for the individual grades. In other words, those people who were enrolled in the tenth, eleventh, or twelfth grade last year and who are not currently enrolled and do not have a diploma.

        In addition to the annual rate, two other estimates of dropouts are frequently used. The annual dropout rate is different from a "pool" (or status) measure such as the proportion of an age group who are high school dropouts (not enrolled in school, not high school graduates, which does not depend on when the individuals dropped out. A third measure of dropouts is the cohort measure, most commonly from a longitudinal study, in which one calculates the proportion of a specific group of people enrolled in a specific year, who had not received diplomas (and who were no longer in school) some years later. For example, the proportion of a cohort enrolled in ninth grade in year X, who were not enrolled and had not received a diploma by year X=4.

School enrollment.  
        The school enrollment statistics from the CPS are based on replies to the interviewer's inquiry whether the person was enrolled in regular school. Interviewers were instructed to count as enrolled anyone who had been enrolled at any time during the current term or school year in any type of public, parochial, or other private school in the regular school system. Such schools include nursery schools, kindergartens, elementary schools, high schools, colleges, universities, and professional schools. Attendance may be on either a full-time, or part-time basis and during the day or night. Regular schooling is that which may advance a person toward an elementary or high school diploma, a college, university, or professional school degree. Children enrolled in nursery schools and kindergarten are included in the enrollment figures for regular schools and are also shown separately.

    Enrollment in schools which are not in the regular school system, such as trade schools, business colleges, and schools for the mentally handicapped, which do not advance students to regular school degrees, is not included.

    People enrolled in classes which do not require physical presence in school, such as correspondence courses or other courses of independent study, and in training courses given directly on the job, are also excluded from the count of those enrolled in school, unless such courses are being counted for credit at a regular school.

School enrollment in year preceding current survey:   An inquiry on enrollment in regular school or college in October of the preceding year was asked for all people (enrolled and not enrolled). In years before 1988, the question was asked only of people who were not currently attending regular school or were enrolled in college. In the tabulations of people enrolled in secondary school in the previous year, people currently enrolled in high school were assumed to have been enrolled the previous year.

Comparability of enrollment data in previous years: Changes in the edit and tabulation packages used in processing the October CPS school enrollment supplement caused some minor revisions in the estimates. The current edit and tabulation package began with 1987 data. The 1986 data which were published in Current Population Report, Series P-20 No. 429, were reprocessed with the rewritten programs in order to clarify comparability. Time series tables usually show only the revised estimates for 1986. The previous edit and tabulation package was used from 1967 to 1986.

        Major changes in the data due to the 1987 edit revisions were: (1) Among 14- and 15-year-olds, an edit improvement allowed people with enrollment data not reported, who were previously automatically imputed "not enrolled," to be enrolled; (2) Revisions in tabulation of enrollment in the previous year simplifies calculation of an annual high school dropout rate; (3) Edit improvements caused increases in college enrollment estimates, most notably above age 24; this age group was largely ignored in earlier edits; (4) Type of college is fully allocated (discussed earlier); (5) Tabulations of type of college (2- year,4-year) are available by race; (6) Dependent family member is defined consistently; (7) New tabulations of employment status, vocational course enrollment, college retention and re-entry, and families with children enrolled in public and private school were available beginning in 1987.

        In the series of reports on school enrollment for 1987 to 1992, race and Hispanic origin were erroneously tabulated for a small percentage of children 3 to 14 years old. Race and Hispanic origin of an adult in the household were attributed to the child, rather than using the child's reported characteristics. In the vast majority of cases these characteristics were the same for family members, but for a small percentage of children, they were different. The correction made the following proportional changes in the numbers of children in each group: White (-0.5 percent), Black (+3.1 percent), Hispanic origin (-4.6 percent).

        Published data on enrollment from the October CPS for 1981 to 1993 used population controls based on the 1980 census. Beginning in 1994 estimates were based on 1990 census population controls, including adjustment for undercount. Time series tables show two sets of data for 1993; the data labeled 1993r were processed using population controls based on the 1990 census, adjusted for undercount. The change in 1994 from a paper and pencil survey to a computer assisted survey had some affect on the data. Most notable, the enrollment question for children 3 to 5 years old was different from the question for older children --it included a reference to nursery school. In 1994 reported nursery school enrollment was significantly higher than in earlier years.

College enrollment.         The college enrollment statistics are based on replies to the interviewer's inquiry as to whether the person was attending or enrolled in school and the grade or school or year of college. Interviewers were instructed to count as enrolled anyone who had been enrolled at any time during the current term or school year, except those who have left for the remainder of the term. Thus, regular college enrollment includes those people attending a 4-year or 2-year college, university, or professional school (such as medical or law school) in courses that may advance the student toward a recognized college or university degree (e.g., BA or MA). Attendance may be either full time or part time, during the day or night. The college student need not be working toward a degree, but he/she must be enrolled in a class for which credit would be applied toward a degree. (see "school enrollment"). Students are classified by year of college, based on the academic year (not calendar year) they are attending. Undergraduate years are the 1st `through 4th year, or freshman through senior. Graduate or professional school years include the 5th year and higher.

Two-year and four-year colleges: College students were asked to report whether the college in which they were enrolled was a 2-year college (junior or community college) or a 4-year college or university. Students enrolled in the first 4 years (undergraduates) were classified by the type of college they reported. Graduate students are shown as a separate group.

Attendance, full-time and part-time. College students were classified according to whether they were attending school on a full-time or part-time basis. A student was regarded as attending college full time if he/she was taking 12 or more hours of classes during the average school week, and part time if he/she was taking less than 12 hours of classes during the average school week.

Vocational school enrollment.     Vocational school enrollment includes enrollment in business, vocational, technical, secretarial, trade, or correspondence courses which are not counted as regular school enrollment and are not for recreation or adult education classes. Courses counted as college enrollment should not also be included as vocational.

School, Level of:     The statistics on level of school indicate the number of people enrolled at each of five levels--nursery school, kindergarten, elementary school (1st to 8th grades), high school (9th to 12th grades), and college or professional school. The last group includes graduate students in colleges or universities. People enrolled in elementary, middle school, intermediate school or junior high school through the eighth grade are classified as in elementary school. All people enrolled in 9th through 12th grade are classified as in high school.

School, Modal grade. Enrolled people are classified according to their relative progress in school: that is, whether the grade or year in which they were enrolled was below, at, or above the modal (or typical) grade for people of their age at the time of the survey. The modal grade is the year of school in which the largest proportion of students of a given age is enrolled.

Head Start.     Children enrolled in Head Start programs or similar programs sponsored by local agencies to provide preschool education to young children are counted under nursery school or kindergarten as appropriate.

School, Nursery.     A nursery school is defined as a group or class that is organized to provide educational experiences for children during the year or years preceding kindergarten. It includes instruction as an important and integral phase of its program of child care. Private homes in which essentially custodial care is provided are not considered nursery schools. Children attending nursery school are classified as attending during either part of the day or the full day. Part-day attendance refers to those who attend either in the morning or in the afternoon, but not both. Full-day attendance refers to those who attend in both the morning and the afternoon. Children enrolled in Head Start programs or similar programs sponsored by local agencies to provide preschool education to young children are counted under nursery school.

School, Public or private.     In this report, a public school is defined as any educational institution operated by publicly elected or appointed school officials and supported by public funds. Private schools include educational institutions established and operated by religious bodies, as well as those which are under other private control. In cases where enrollment was in a school or college which was both publicly and privately controlled or supported, enrollment was counted according to whether it was primarily public or private.