A note on methodology: best colleges for adult learners.

We began with the 7,647 postsecondary institutions listed in the Integrated Postsecondary Education Data System (IPEDS) as being active in the 2015-16 academic year. We then limited the sample to all colleges with a Carnegie basic classification in 2015 of between 1 and 23, excluding many colleges that only grant certificates as well as special-focus institutions such as medical schools or rabbinical programs. We dropped fifty-eight colleges for being outside the fifty states and Washington, D.C., dropped nine colleges for closing or merging since 2015-16, dropped four colleges for not participating in any federal financial aid programs, and dropped the five service academies to be consistent with the main rankings. An additional 133 colleges were excluded for having fewer than 100 students in any of the last three years in which they were open.

The next sample restriction was to exclude colleges that did not have data on all of the outcome measures. Another 587 colleges were dropped for not participating in the College Board's Annual Survey of Colleges, which is key in our rankings. Fifty-seven colleges did not have data on the percent of adult students, 287 colleges did not have data on average earnings of independent students, and we excluded thirty-eight colleges that participated in the federal student loan program but did not report a separate repayment rate for independent students. As we used the percentage of adult students as one of our metrics, colleges with insufficient numbers of independent students to have a separate repayment rate for independent students were unlikely to score highly in this ranking anyway. For twenty colleges that served at least 75 percent adult students and did not have separate data on earnings or repayment rates for independent students, we instead used data for all students. Our resulting sample is 2,425 colleges, of which 1,133 are considered four-year colleges (based on Carnegie classification and whether they awarded more bachelor's degrees than certificates or associate's degrees) and 1,292 are two-year colleges.

We used the same seven metrics in this year's rankings as we did in our inaugural rankings for adult students in 2016. They are the following:

(1) Ease of transfer/enrollment. This is designed to reflect how easy it is for adult students to either initially enroll or transfer in a given college. It includes data from the U.S. Department of Education's Integrated Postsecondary Education...