National Center for Education Statistics

What is the difference between the ACGR and the AFGR?

By Joel McFarland

NCES and the Department of Education have released national and state-level Average Cohort Graduation Rates for the 2015-16 school year. You can see the data on the NCES website (as well as data from 2010-11 through 2014-15).

In recent years, NCES has released two widely-used annual measures of high school completion: the Adjusted Cohort Graduation Rate (ACGR) and the Averaged Freshman Graduation Rate (AFGR). Both measure the percent of public school students who attain a regular high school diploma within 4 years of starting 9th grade. However, they also differ in important ways. This post provides an overview of how each measure is calculated and why they may result in different rates.

What is the Adjusted Cohort Graduation Rate (ACGR)?

The ACGR was first collected for 2010-11 and is a newer graduation rate measure. To calculate the ACGR, states identify the “cohort” of first-time 9th graders in a particular school year, and adjust this number by adding any students who transfer into the cohort after 9th grade and subtracting any students who transfer out, emigrate to another country, or pass away. The ACGR is the percentage of the students in this cohort who graduate within four years. States calculate the ACGR for individual schools and districts and for the state as a whole using detailed data that track each student over time. In many states, these student-level records have become available at a state level only in recent years. As an example, the ACGR formula for 2012-13 was calculated like this:

Average Cohort Graduation Rate calculation

What is the Averaged Freshman Graduation Rate (AFGR)?

The AFGR uses aggregate student enrollment data to estimate the size of an incoming freshman class, which is compared to the number of high school diplomas awarded 4 years later. The incoming freshman class size is estimated by summing 8th grade enrollment in year one, 9th grade enrollment for the next year, and 10th grade enrollment for the year after, and then dividing by three. The averaging of the enrollment counts helps to smooth out the enrollment bump typically seen in 9th grade. The AFGR estimate is less accurate than the ACGR, but it can be estimated as far back as the 1960s since it requires only aggregate annual counts of enrollment and graduate data. As an example, the AFGR formula for 2012-13 was:

Average Freshman Graduation Rate calculation

Why do they produce different rates?

There are several reasons the AFGR and ACGR do not match exactly.

  • The AFGR’s estimate of the incoming freshman class is fixed, and is not adjusted to account for students entering or exiting the cohort during high school. As a result it is very sensitive to migration trends. If there is net out-migration after the initial cohort size is estimated, the AFGR will understate the graduation rate relative to the ACGR. If there is net in-migration, the AFGR will overstate the graduation rate;
  • The diploma count used in the AFGR includes any students who graduate with a regular high school diploma in a given school year, which may include students who took more or less than four years to graduate. The ACGR includes only those students who graduate within four years of starting ninth grade. This can cause the AFGR to be inflated relative to the ACGR; and
  • The AFGR’s averaged enrollment base is sensitive to the presence of 8th and 9th grade dropouts. Students who drop out in the 8th grade in one year are not eligible to be first-time freshmen the next year, but are included in the calculation of the AFGR enrollment base. At the same time, 9th grade dropouts should be counted as first-time 9th graders, but are excluded from the 10th grade enrollment counts used in the AFGR enrollment base. Since more students typically drop out in 9th grade than in 8th grade, the overall impact is likely to underestimate the AFGR enrollment base relative to the true ACGR cohort.

At the national level, these factors largely balance out, and the AFGR closely tracks the ACGR. For instance, in 2012-13, there was less than one percentage point difference between the AFGR (81.9%) and the ACGR (81.4%). At the state level, especially for small population subgroups, there is often more variation between the two measures.

On the NCES website you can access the most recently available data for each measure, including 2015-16 adjusted cohort graduation rates and 2012-13 averaged freshman graduation rates. You can find more data on high school graduation and dropout rates in the annual report Trends in High School Dropout and Completion Rates in the United States.

This blog was originally posted on July 15, 2015 and was updated on February 2, 2016 and December 4, 2017.

Expanding Student Success Rates to Reflect Today’s College Students

By Gigi Jones

Since the 1990s, the Integrated Postsecondary Education Data System (IPEDS) has collected and published graduation rates for colleges and universities around the country. These rates were based on traditional college students—first-time, full-time degree- or certificate-seeking undergraduate students (FTFT) who, generally, enrolled right after high school.

While these data are insightful, some have argued the FTFT graduation rate only provides a part of the picture because it doesn’t consider non-traditional students, including those who are part-time students and transfers. This is an important point because, over the past decade, the number of non-traditional students has outpaced the increase in traditional students, mostly driven by growth in those who have transferred schools.  

The new IPEDS Outcome Measures survey was designed to help answer these changes. Starting with the 2015-16 collection cycle, entering students at more than 4,000 degree-granting institutions must be reported in one of four buckets, also called cohorts (see Figure below).

The FTFT cohort is similar to what has been collected since the 1990s, but the Outcome Measures adds three new student groups to the equation: 

  • First-time, part-time students (FTPT), who attend less than a full-time credit workload each term (typically less than 12-credits) and who have no prior postsecondary attendance; 
  • Non-first-time students, also known as transfer-in students, who are enrolled at a full-time level (NFTFT); and
  • Non-first-time students, also known as transfer-in students, who are enrolled at a part-time level (NFTPT).

For these four cohorts, postsecondary institutions report the awards conferred at two points of time after the students entered the institution: 6 years and 8 years. If students did not receive an award, then institutions must report their enrollment status one of three ways: 1) Still enrolled at the same institution; 2) Transferred out of the institution; or 3) Enrollment status is unknown.

These changes help respond to those who feel that the FTFT graduation rates do not reflect the larger student population, in particular public 2-year colleges that serve a larger, non-traditional college student population. Since 2008, steps have been taken to construct and refine the data collection of non-traditional college students through a committee of higher education experts (PDF) and public Technical Review Panels (see summaries for panels 37, 40 and 45).

The 2016-17 preliminary Outcome Measures data were released on October 12, as part of a larger report on IPEDS winter data collection. The data for individual schools can be found on our College Navigator site.  The final data for 2015-16 will be released in early 2018. Sign up for the IES News Flash to be notified when the new data are released or follow IPEDS on Twitter. You can also visit the IPEDS Outcome Measures website for more information. 

While this is an important step in the process, we are continuing to improve the data collection process. Starting with the 2017-18 Outcome Measures collection, the survey includes more groups (i.e., Pell Grant v. Non-Pell Grant recipients), a third award status point (4-years after entry), and the identification of the type of award (i.e., certificates, Associate’s, and Bachelor’s). Watch for the release of these data in fall 2018. 

EDITOR'S NOTE: This post was updated on October 12 to reflect the release of Outcome Measures data.

A Fresh Look at Homeschooling in the U.S.

By Sarah Grady

From 1999 to 2012, the percentage of students who were homeschooled doubled, from an estimated 1.7 percent to 3.4 percent. But that increase appears to have leveled off, according to newly released data. In 2016, about 1.7 million students (ages 5-17) were estimated to be homeschoolers, which translates to about 3.3 percent of all K-12 students. This rate is not statistically different from the percentage in 2012.

* Statistically adjusted
SOURCE: U.S. Department of Education, National Center for Education Statistics, Parent Survey of the National Household Education Surveys Program (NHES), 1999; Parent and Family Involvement in Education Survey of the NHES, 2003, 2007, 2012, and 2016.

These data come from the recently released First Look report on the Parent and Family Involvement in Education (PFI) survey from the National Household Education Surveys Program (NHES). In this survey, parents were asked a number of questions about their child’s education. Using these data, NCES is able to identify students who are schooled at home instead of school for some or all classes.[1]

So, why did parents say they homeschooled their kids? The most important reason for homeschooling in 2016 was “concern about the school environment, such as safety, drugs, or negative peer pressure,” reported by 34 percent of parents of homeschooled students. (This was also the most commonly reported reason selected by parents in 2012.)  Other reasons cited as most important by families of homeschooled students in 2016 were dissatisfaction with academic instruction at other schools (17 percent of homeschooled students’ parents) and a desire to provide religious instruction (16 percent).

The PFI survey is uniquely suited to collect data about homeschooled students because it collects data from households rather than schools or other institutions. It includes a suite of surveys designed to capture data related to learning at all ages and is ideal for trend analyses because of the repeated measures over time. The NHES:2016 First Look report for the PFI data also provides key estimates related to school communication with parents, homework, parents’ involvement in their students’ education, and homeschooling. The data will be available to researchers in the coming months. Check the NHES website for updates.


[1]Students who are homeschooled primarily because of a temporary illness and students who attend school for more than 25 hours per week are not counted in NCES’s estimate of homeschooling.  

New Data Explore Adults’ Nondegree Credentials

By Lisa Hudson

Despite a national interest in nondegree credentials—such as postsecondary certificates, occupational certifications, and occupational licenses—there hasn’t been comprehensive, national data on these programs. However, a new report from NCES fills this gap using data from our new Adult Training and Education Survey (ATES).

These data show that 27 percent of adults have a nondegree credential and that 21 percent have completed a work experience program (such as an apprenticeship or internship). The ATES data also show that the completion of degree programs and nondegree programs are related. For example, having a certification or license is more common among adults who have a college degree than among adults with lower levels of education.  

The ATES is one component of the NCES National Household Education Surveys Program (NHES), which collects information on education-related topics that cannot be addressed through school-based surveys. It includes a suite of surveys designed to capture data related to learning at all ages. This most recent NHES administration, conducted from January to September 2016, was the first administration of the ATES. This survey was completed by a national sample of about 47,700 adults between the ages of 16 and 65.

The data show that nondegree credentialing and work experience programs are particularly common in the health care field. In fact, health care was the most common field in which both certifications and licenses were held, and the most common field for which adults had completed a work experience program.

The ATES also found that adults perceive nondegree credentials to be useful for many labor market outcomes. For example, 82 percent of adults who have a certification or license reported that it was very useful for “getting a job”, 81 percent reported that it was very useful for “keeping you marketable to employers or clients”, and 66 percent reported it that was very useful for “improving your work skills” (see figure). 

The ATES data will be available to researchers in the coming months. Check the NHES website for updates.

Getting to Know and Use the Integrated Postsecondary Education Data System

By Sarah Souders

More than 3,915,918 individuals were employed by degree-granting postsecondary institutions in 2015. These employees provided services and support to the 19,977,270 students attending the nation’s 4,562 degree-granting institutions.

We know this information—and much more—because of the Integrated Postsecondary Education Data System (IPEDS), a program in the National Center for Education Statistics (NCES). In fact, these data points only scratch the surface of information collected and updated annually by IPEDS. Each year, IPEDS issues 12 surveys to all postsecondary institutions receiving Title IV Federal Aid[1] and some institutions that participate by choice. The surveys provide data on a broad range of topics, from enrollment, admissions, and cost to grad rates, faculty, and human resources.  These data are reported by gender, race/ethnicity, institution type, and more.

But we don’t just want people to know about the data – we want them to use it!

The “Use the Data” landing page (see image below) provides many options for analysis. Users can look up and compare institutions, view trends and statistical tables for specific data points, download a complete survey file, customize a data file, or download a report summarizing the data for specific institutions.

Screen shot of IPEDS Use the Data website

There are many options for analysis given the extensive data collection and number of tools. One tool, the IPEDS Trend Generator, allows users to select a subject and question to observe trends over time. The trend generator allows users to explore enrollment trends, among many other topics.

Below is an example of a bar graph that can be generated using this tool. With the click of a couple of buttons, you can quickly learn that the number of students attending postsecondary institutions (as measured by 12-month enrollment) has been declining in recent years, after peaking in 2010-11 at 29,522,688 students. By 2014-15, enrollment decreased to 27,386,275 students, a decline of more than 2 million students.  

In addition to producing graphical displays, data from the Trend Generator can quickly be exported to an Excel file.

Chart showing trend data on postsecondary enrollment

Users also have the option to create custom data files which can be exported to Excel, SAS, STATA, or SPSS files. Users can choose individual or specific institutions using their own criteria, or groups of similar institutions can be selected at once by using predetermined categorizations. Some pre-set groupings include whether the institution is the state’s land grant institution, a Historically Black College and University, or a tribal college. Institutional groupings can also be selected by geographic characteristics and other groupings, such as highest degree offered, availability of distance education, and Carnegie classification. The full list of institutional groupings can be found on the IPEDS website

After selecting the institutions, users can choose the variables to be analyzed. In the screenshot below, you can see that the variable “number and salaries of non-medical full-time staff” allows users to select breakouts by academic rank, such as professor, associate professor, lecturer, etc. These breakouts can provide greater detail with regard to current and average salary. Once the variables are selected, the desired data file is complete and can be exported into one of the available formats.

Screenshot of IPEDS categories

The Integrated Postsecondary Education Data System contains a multitude of data which can be accessed for all levels of analysis, whether you are an experienced statistician or just a casual user. If you are using the data and have questions or comments, contact the IPEDS Help Desk by phone at 1-877-225-2568 or by email: .

Sarah Souders was a 2017 summer intern for NCES. She is a student at The Ohio State University. 

[1] Title IV of the HEA authorizes the federal government’s primary student aid programs, which are the major source of federal support to postsecondary students. Title IV aid includes programs like Pell Grants, Stafford Loans, Perkins Loans, Supplemental Educational Opportunity Grants, and Federal Work Study. If an institution accepts aid from programs authorized by Title IV of the Higher Education Act of 1965, as amended (20 USC 1094, Section 487(a)(17) and 34 CFR 668.14(b)(19)), then they are required to complete all IPEDS surveys.