Understanding Four- vs. Six-Year College Graduation Rates

If you’ve been shopping for colleges you might have read about four and six year graduation rates. These rates are indicators of what percentage of entering freshmen finish college four years after starting and what percentage finish six years after starting. Graduation rates beyond six years aren’t followed very closely, as most students finish within six years or not at all, and from the numbers I’ve seen, five and six year graduation rates tend to be very similar.

“Time-to-Graduation too Often Overlooked” by Beth Akers and Matthew M. Chingos addresses the issue of time to graduation as a significant concern for students considering a college. They are concerned about the added costs involved in graduating six years after starting rather than four. Akers and Chingos provide a lot of useful data indicating that four and six year graduation rates can vary widely among institutions regardless of the institution’s quality on other measures, including the strength of incoming students’ ACT or SAT scores. Apparently, there’s no clear correlation among student scores, institutional quality, and differences between four- and six-year graduation rates:

One might assume that general metrics of college quality are good proxies for all sorts of outcomes, including time-to-degree. For example, perhaps institutions with good six-year graduation rates also have good four-year graduation rates so it doesn’t really matter which one students use.  But it turns out that this is not the case.  The average time-to-degree varies widely, even within institutions that seem to be of similar quality based on other measures.

What I would like to do here is help students think through why graduation rates might differ from school to school and how to evaluate those differences.

First, I agree with the basic point of both articles: students need to do all that they can to graduate in four years, because by doing so they’re saving money. These cost savings take the form of not paying for two years of additional tuition, room, board, and fees, and also in the form of two fewer years of lost income. The sooner you start work after college, the sooner your investment in college starts paying you back.

But it’s very important that we understand the range of possible reasons for these differences. Time to graduation is always just a matter of basic math: any four-year college that requires 120 credit hours to graduate requires 30 credits per year, or 15 credits (typically five classes) per semester. If a student passes five classes per semester every semester they will graduate in four years, period. So if 15-20% of a college’s students need an additional two years to graduate that’s not because of the degree structure or the college itself unless significantly more than 120 credits are required for graduation.

Typical reasons that cause students to take more than four years to graduate include:

1. Failing or dropping classes — do this four or five times and you’ve added a semester to your completion time.
2. Sports injuries, if they cause you to drop out of school for a semester or more.
3. Serious family issues or illnesses, if they cause you to drop out of school for a semester or more.
4. Switching majors during or after your third year.
5. Adding minors, especially multiple minors.
6. Double majors.

At the end of this current semester of teaching, I have students who fit most if not all of the above categories.

Institutional reasons include:

7. Credit-intensive majors. The college usually can’t do anything about these requirements, as they are field-specific and are usually designed to meet state or federal requirements. For example, education majors at my current institution are all required to do coursework about equivalent to a double major. Those requirements are imposed by the state. Just know what you’re getting into if you select one of these majors.
8. The school doesn’t accept many or any transfer credits or students (i.e., most students start as freshmen), which raises the likelihood of more than four years to graduation. Transfer students will finish in two or three years, and if they graduate in four, they may have done it in four years at that institution but have taken much more than four years to get their degree.

Since my original draft, readers have suggested the following reasons for increased time to graduation.

9. One reader suggested that time to graduation may be increased if an institution has a significant population of non-traditional students, such as working adults. Working adults are often unable to attend full time so take longer to complete. My own alma mater, Rollins College, has an undergraduate evening program called the Hamilton Holt School that is largely populated by non-traditional students along with graduate programs with a similar student population. I suspect this school contributes to the 15% increase in six year graduation rates over four year graduation rates at Rollins College. I was one of these students. It took me nine years to complete my B.A. at three different institutions. I just happened to finish at Rollins College.
10. A college with a high population of remedial students will have longer time to graduation, as these courses often do not count for credit toward graduation. If a student has to take four remedial classes in two or three different subjects, that’s a semester added to their time to graduation. This problem may not be a negative if the college serves its remedial students well.
11. Are the college’s general education courses filled to overflowing? Do they offer too few sections for the students who need them? This problem is institutional and can extend time to graduation.
12. Does the college serve many veterans or those in the military? They often have to take a semester or more off for service. It’s a good thing that the college does so, but serving this population will affect a college’s stats on time to graduation.

So even if you see that there’s a big disconnect between four- and six-year graduation rates, you still don’t know what that means. If it’s because many students fail their classes, that means the school has meaningful academic standards but a weak student population, which is a mixed signal (bad in that students are weak, good in that at least the school has academic standards). If there’s a big difference between four- and six-year graduation rates because many students take credit-intensive majors or double majors, that’s a sign that the school has a high population of very motivated students, or very strong programs in credit-intensive majors, so that’s a good sign. Schools with a high four-year graduation rates may have low academic standards, and faculty may be pressured to just pass everyone through, in which case a high four-year graduation rate can be a sign of a bad school. If the school has an evening program populated by working adults, then differences in four- and six-year graduation rates don’t tell you anything at all.

So finding out why these differences exist is what matters. The best thing to do is to consider this measure alongside many others, and compare your potential college’s graduation rates to national averages and other potential colleges. If they’re above the national average for their cohort, you’re on safe ground.

In general, four-year private non-profit institutions have the best four- to six-year graduation rates, and for-profit institutions have the worst, running at about half the rate of public and private non-profit institutions.