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Public High School Dropouts and Completers from the Common Core of Data: School Years 1991-92 through 1997-98

  Introductory Material
Section A
Section B
   1997–98 Dropouts and Completers
Section C
   Dropouts: Changes Over Time by Selected Characteristics
Section D
   High School Completers: Trends and Selected Characteristics
Section E
   Basic Tables
Section F
   Technical/Methodological Issues
   Additional Tables
PDF File (1,026 KB)

Lee Hoffman

Section F. Technical/Methodological Issues

  1. History of the CCD Dropout and Four-year Completion Rate Statistics Dropouts
  2. Technical Notes
  3. Glossary of Terms
  4. Other Resources

I. History of the CCD Dropout and Four-year Completion Rate Statistics Dropouts

Because of the demand for a standard national dropout statistic, in 1986, the National Center for Education Statistics (NCES) began work to examine its collection of elementary and secondary education data reported from the administrative records of public schools and agencies. One recommendation from this examination was that NCES add a dropout count to the Common Core of Data (CCD), with the caveat that states would have to adopt a nationally consistent definition of "dropout" in order for this new statistic to be usefully comparable.

The Hawkins-Stafford School Improvement Amendments of 1988 directed the Commissioner of Education Statistics to establish a federal-state cooperative education statistics system that would improve the quality of education data for policymaking at national, state, and local levels. The same legislation required the Commissioner to report to Congress each year on the second Tuesday after Labor Day about the rate of school dropouts and completions in the nation (under current legislation, this report is no longer mandatory).

The interest in nationally uniform, state-comparable dropout statistics converged from several sources, and NCES responded with a coordinated program of activities. Beginning in September 1989, NCES published a national dropout and completions report based on information from the October 1988 Current Population Survey of the Bureau of the Census and information from NCES' own longitudinal High School and Beyond Study. NCES continues this yearly report through the present. It provides a consistent picture of national and regional dropout rates over time, and applies a uniform definition of "dropout." However, neither the Current Population Survey nor any of NCES' longitudinal surveys employs a sample that is large enough to provide single year state-representative findings.

Working with states through the National Forum on Education Statistics, NCES formulated a dropout definition. Those who participated in developing the definition recognized that a field test was needed to determine whether school districts actually could collect the data as specified. There was also a secondary question of which membership count to use as the denominator. Theoretically, a count of students in membership at the end of the school year could be preferable because it would assign students who transferred during the year to the school district that received them. However, the CCD only collects an October 1 membership count. The effect of using a beginning- or end-of-school-year membership count on the size of the dropout rate had to be tested before deciding whether to add the burden of an extra, end-of-year membership count.

In the 1989–90 school year, a sample of volunteering school districts from 26 states, the District of Columbia, and two outlying areas carried out a field test of the proposed dropout collection. Researchers visited school sites, analyzed findings, and tracked a number of school leavers to determine whether districts could accurately distinguish dropouts from students who had left for other reasons. The overall findings of this assessment were that school districts generally reported accurate counts and that there was no meaningful difference between rates calculated on the basis of fall or end of year membership counts.

A field test was also done during the 1989–90 school year (Hoffman 1995). The participants were in approximately 300 school districts that included representatives from 27 states and 2 outlying areas. The data were gathered through administrative records maintained at school districts and schools. The field test data were used to inform the design of a dropout statistics component for the CCD.

The collection was initiated with a set of instructions to state CCD coordinators in the summer of 1991. Those instructions specified the details of dropout data to be collected during the 1991–92 school year. Dropouts, like completers, are reported for the preceding school year. The 1991–92 data were submitted to NCES as a component of the 1992–93 CCD data collection. Most recently, the 1997–98 dropout data were submitted as a component of the 1998–99 CCD collection.

The definition that was agreed upon by NCES and the states was the following:

CCD definition of dropout. The denominator of the rate is the October 1 membership count for the state. The numerator (dropouts) are all individuals who:

  • Were enrolled in school at some time during the previous school year;
  • Were not enrolled at the beginning of the current school year;
  • Have not graduated from high school or completed a state- or district-approved educational program; and
  • Do not meet any of the following exclusionary conditions: transfer to another public school district, private school, or state- or district-approved education program; left the country; temporary absence due to suspension or school-approved education program; or death.

For the purpose of this definition:

  • The school year is the 12-month period of time from the first day of school (operationally set as October 1), with dropouts from the previous summer reported for the year and grade in which they fail to enroll;
  • Individuals who are not accounted for on October 1 are considered dropouts;
  • An individual has graduated from high school or completed a state- or district-approved educational program upon receipt of formal recognition from school authorities. A state- or district-approved educational program may consist of special education and district or state-sponsored GED preparation.

As in developing any nationally consistent definition, there was considerable variation in the operationalization of the dropout definition across local, state, and federal data collections. Some of the more difficult decisions made for the CCD dropout definition were the following:

  • Those who return to school after October 1 are identified as dropouts;
  • Those who complete a grade and drop out over the summer are attributed to the grade and school year to which they fail to return;
  • Students entering adult education GED programs are considered dropouts; and
  • A student who drops out more than once can be counted as a dropout only once in a given school year, but in every school year that he or she drops out.

Addition of states with July–June reporting calendars. In the late 1990s technical work was done to evaluate the quality of dropout data in the CCD and to determine whether it was feasible to compensate for inconsistencies in states' reporting practices (Winglee et al. 2000). One of the findings that came out of the report was that the types of noncompliant practices have different effects on the dropout rate. The dropout statistic developed followed an October through September school year because in the field test, it was determined that the majority of states followed this calendar. The practice of reporting on a July–June calendar (in which the dropout status is determined on the last day of the school year rather than the first day of the following school year) is the most common departure from the CCD definition. This practice typically leads to over-reporting of dropouts, although the net effects on the dropout rates are small. Three factors were considered in reviewing the findings of this study: data quality, feasibility of obtaining data, and the usefulness of resulting information. The report found that on the whole, accepting dropout data from states that use the July–June calendar was the best compromise among all three. The noncompliant practice of omitting adult GED students from the dropout count is less common, but is associated with substantial underreporting of dropouts. The effects associated with attributing summer dropouts to the previous school year and grade are more variable. The report concluded that although it is possible to achieve comparability by adjusting data, NCES should continue to press for adoption of a standard practice of reporting GED and summer dropouts.

In 1997–98, a total of 48 states, including the District of Columbia, and all the outlying areas submitted dropout data to the CCD. A recent analysis of the data from all participating states has led NCES to conclude that the possible discrepancies introduced by the 12 states that reported dropouts from July through June, rather than October through September, are small enough to justify the inclusion of the dropout data from these states.

As this process progresses further, there will, no doubt, be some discontinuities in dropout reporting as more consistent data become available.

Dropout rate. The CCD high school dropout rates for grades 9 through 12 are defined as the percentage of high school dropouts for a given school year among all high school student members enrolled on October 1 of the same school year. The state dropout rate is computed using the district level data in the CCD agency (school district) file by using a composite estimate as follows:

Dropout rate - Composite Estimate

Comparability of data has always been a strict criterion for publishing CCD dropout information. However, in 2000, NCES determined that one of the most common departures from the standard definition did not have an appreciable effect upon the numbers of dropouts reported for a school year. This variation consisted of states following a July–June reporting calendar rather than the October–September calendar of the CCD. These "alternative calendar" states, as they were labeled, determined a student's dropout status at the end of the school year in which he or she had left, not at the beginning of the subsequent school year. These "alternative calendar" states' data are reported for 1993–94 through 1997–98.

High School Completers

High school completion rates go hand in hand with dropout rates. The more widely the CCD dropout rate was adopted, the more users asked for a high school completion rate. NCES again worked with states to develop and test a high school completion rate using CCD data already being collected.

High school completion definition. The number of high school completers has been collected on the CCD since the 1987–88 school year. The statistic is collected at both the agency and state level. There are two types of completers collected at the agency level: diplomas, both regular and other; and other high school completers. Other high school completers may include certificates of attendance, Individualized Education Program completions, certificates, etc. At the state level, high school equivalencies are collected in addition to these categories (but not used in this report). Since state and local policy determine what types of high school requirements and credentials are used, keep in mind that these types of completer categories may not be comparable across states.

High school four-year completion rate. The CCD has the capacity to provide annual four-year completion rates by state. Bose and Hoffman (1997) presented eight potential rates through which the CCD data can be used to give an estimate of high school completion. They compared each of these rates against a cohort rate (obtained by following a cohort of students entering high school) and suggested a four-year completion rate based on counts of high school completers and dropouts.

In the late 1990s, a technical report was done to test the Bose and Hoffman (1997) recommended method of calculating a high school four-year completion rate using the CCD, and whether the CCD could provide an annual four-year completion rate by state. One of the major conclusions of this study was that the CCD can provide annual statistics of high school four-year completion rates by state.

The method used to calculate a CCD four-year completion rate emulates a true cohort approach that follows students through 4 years of high school. For simplicity, the following expression shows the method of calculation using composite data at the state level. The four-year completion rate, for state s at year t is:

High school four-year completion rate - Method of calculation using composite data at the state level

The number of completers is summed from the district level data in the CCD agency file. To compute the 1997 four-year completion rate, for example, the required data elements are: the counts of 1997 completers, the 1997 grade 12 dropouts, the 1996 grade 11 dropouts, the 1995 grade 10 dropouts, and the 1994 grade 9 dropouts. This method provides a good estimate of completions but requires data from four consecutive years.

II. Technical Notes

How does the CCD dropout rate compare with other rates? NCES publishes three types of dropout rates.

Event rates describe the proportion of students who leave school each year without completing a high school program. This annual measure of recent dropout occurrences provides important information about how effective educators are in keeping students enrolled in school. Event rates are collected through the CCD and the Current Population Survey (CPS).

Status rates provide cumulative data on dropouts among all young adults within a specified age range. Status rates are higher than event rates because they include all dropouts regardless of when they last attended school. Since status rates reveal the extent of the dropout problem in the population, these rates also can be used to estimate the need for further education and training designed to help dropouts participate fully in the economy and life of the nation. Status rates for young adults ages 16 through 24 are collected through the CPS.

Cohort rates measure what happens to a group of students over a period of time. These rates are based on repeated measures of a cohort of students with shared experiences and reveal how many students starting in a specific grade drop out over time. Typically, data from longitudinal studies provide more background and contextual information on the students who drop out than are available through the CPS or CCD data collections. Cohort rates were collected through the National Education Longitudinal Survey (NELS) 1988, and are included in subsequent longitudinal files.

The dropout collection through the CCD is designed to be consistent with the current CPS procedures. However, there are differences in dropout collection procedures between the two data sets. First, the CCD represents a state's public school dropout counts; in other words, the dropout rate represents the number of public school students who have dropped out over the total number of public school students enrolled in the state. This differs from the CPS dropout counts in a few ways. The CPS counts include students who were enrolled in either public or private schools. Secondly, the CPS is a count of young adults who live in the state, not necessarily those who went to school in that state. The third difference between CPS and CCD dropout collection procedures is that the CCD collection includes dropouts from grades 7 through 12 versus only grades 10 through 12 in the CPS (although CCD event rates focus on grades 9 through 12 in this report). Fourth, the CCD collection is based on administrative records rather than a household survey as in CPS. One other difference is that, in contrast to the CPS, the CCD collection counts those students who leave public school to enroll in GED programs (outside the public education system) as dropouts. Finally, the CPS is not traditionally used to report state-level estimates.

Why did NCES choose this completion rate?In the late 1990s, NCES convened a group of states to explore whether a completion rate based upon data available through the CCD would be technically and practically feasible. Eight potential rates were identified from various state reporting systems that met these criteria. Two of the potential rates that were tested involved students divided by completers (one being completers divided by 12th graders and the other being completers divided by the number of 9th graders 4 years ago). The 12th grade rate was found to be less than credible because many students who drop out do so before 12th grade. The 9th grade rate was considered to be biased by migration and retention "bulges" (i.e., membership in 9th grade is often greater than that in 8th or 10th grades because of students who repeat the 9th grade). The idea of the 9th grade rate was taken into consideration when developing the recommended rate used in this report. By including dropouts over a 4-year period, this rate incorporates the idea of catching all those students who left in a 4-year period (as a true 9th grade cohort would also do). The rate is easy to explain to general audiences and easy to calculate using existing CCD data. It also does not penalize those districts who keep students in school even though it may take more than 4 years for them to complete a high school education.

How does the CCD four-year completion rate differ from the CPS completion rate?Many of the differences between the CCD and CPS dropout collections are also evident in their respective reports of high school completion. There are additional distinctions, however. The CCD is more of an accountability measure for states while the CPS measure defines a population. The main difference is that the CCD four-year completion rate is a leaver rate, of those that leave school, how many completed. The CPS measures an age group of the population (in NCES' case 18- to 24-year-olds) and asks if they graduated from school. Thus, the CCD estimates a cohort completion rate for those who have left school, while the CPS provides a status rate based on the total young adult population.

National totals. Because not all states report dropouts in agreement with the CCD definition, the CCD cannot provide national totals for dropout or completion rates. It is also not advisable to create "reporting state" totals, because the bias introduced by those states that are missing is unknown. When all states are able to report to NCES using the CCD dropout definition, a national total of dropouts and completers can and will be reported.

III. Glossary of Terms

American Indian/Alaska Native: A person having origins in any of the original peoples of North America, and who maintains cultural identification through tribal affiliation or community recognition.

Asian/Pacific Islander: A person having origins in any of the original peoples of the Far East, Southeast Asia, the Indian subcontinent, or the Pacific Islands. This includes, for example, China, India, Japan, Korea, the Philippine Islands, and Samoa.

Black: A person having origins in any of the Black racial groups of Africa.

Completer, High School: Student who has received a certificate of attendance or other certificate of completion in lieu of a diploma during the previous school year and subsequent summer school.

Diploma, High School: A formal document certifying the successful completion of a secondary school program prescribed by the state education agency or other appropriate body.

Diploma Recipients: A student who has received a diploma during the previous school year or subsequent summer school. This category includes regular diploma recipients and other diploma recipients.

Education Agency: A government agency administratively responsible for providing public elementary and/or secondary instruction or educational support services.

General Education Development (GED) Test: A comprehensive test used primarily to appraise the educational development of students who have not completed their formal high school education, and who may earn a high school equivalency certificate through achievement of satisfactory scores.

Graduate, High School: A high school graduate is defined as an individual who received a diploma recognizing the completion of secondary school requirements during the previous school year and subsequent summer school. It excludes high school equivalency and other high school completers (e.g., those granted a certificate of attendance).

High School Completer: Includes individuals who received a diploma as well as those other credentials in lieu of a diploma. It excludes high school equivalencies.

High School Equivalency Certificate: A formal document certifying that an individual met the state requirements for high school graduation equivalency by obtaining satisfactory scores on an approved examination, and meeting other performance requirements (if any) set by a state education agency or other appropriate body.

High School Equivalency Recipient: Individual age 19 years or younger who received a high school equivalency certificate during the previous school year or subsequent summer. Item was last reported on the Local Education Agency Survey in 1990–91, but continues to be collected by the State Nonfiscal Survey.

Hispanic: A person of Mexican, Puerto Rican, Cuban, Central or South American, or other Spanish culture or origin, regardless of race.

Locale Code: An indication of an agency's location relative to a center of population. The agency code is calculated from the locale codes of the schools in the agency.

Large City: A central city of a consolidated metropolitan statistical area (CMSA) or metropolitan statistical area (MSA), with the city having a population greater than or equal to 250,000.

Mid-size City: A central city of a CMSA or MSA, with the city having a population less than 250,000.

Urban Fringe of a Large City: Any incorporated place, Census designated place, or non-place territory within a CMSA or MSA of a large city and defined as urban by the Census Bureau.

Urban Fringe of a Mid-size City: Any incorporated place, Census designated place, or non-place territory within a CMSA or MSA of a mid-size city and defined as urban by the Census Bureau.

Large Town: An incorporated place or Census designated place with a population greater than or equal to 25,000 and located outside a CMSA or MSA.

Small Town: An incorporated place or Census designated place with population less than 25,000 and greater than or equal to 2,500 and located outside a CMSA or MSA.

Rural, outside MSA: Any incorporated place, Census designated place, or non-place territory not within a CMSA or MSA of a large or mid-size city and defined as rural by the Census Bureau.

Rural, inside MSA: Any incorporated place, Census designated place, or non-place territory within a CMSA or MSA of a large or mid-size city and defined as rural by the Census Bureau.

The assignment is made on the locale codes assigned to the majority of schools in the agency.

State Education Agency: An agency of the state charged with primary responsibility for coordinating and supervising public instruction including setting of standards for elementary and secondary instructional programs.

Student: An individual for whom instruction is provided in an elementary or secondary education program that is not an adult education program and is under the jurisdiction of a school, school system, or other education institution.

White: A person having origins in any of the original peoples of Europe, North Africa, or the Middle East.

IV. Other Resources

CCD Web Site:

Bose, J. and Hoffman, L. April 1997. Developing a High School Graduation Rate Using CCD Data: Discussion Paper for April 1997 EIAC Meeting. NCES.

Hoffman, L. 1995. State Dropout Data Collection Practices: 1991–1992 School Year. NCES 95–690.

Kaufman, P., Klein, S., Kwon, J., Klein, S., and Chapman C. 2001. Dropout Rates in the United States: 1999. NCES 2001–022.

Winglee, M., Marker, D., Henderson, A., Young, B., and Hoffman, L. 2000. A Recommended Approach to Providing High School Dropout and Completion Rates at the State Level. NCES 2000–305.

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7 The term "graduate" was used in the original technical report, "completers" is used in this report to more accurately describe the completion population.

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