Which college graduates will earn enough to pay off their loans? Using PayScale data, SmartMoney looked at college costs and median alumni income two years and 15 years after graduation to calculate the return on investment.

For example, a hypothetical grad who spent $100,000 to attend college and now earns $150,000 a year would score 150. The higher the score, obviously, the better.

The payback rankings show flagship state universities provide faster payback than the high-priced Ivy League or other high-end private institutions. Ivy Leaguers earn more, but they paid a lot more. Georgia Tech, a public university that educates many engineers, has the highest payback rank at 221, followed by the University of Texas at Austin. Sarah Lawrence, a very expensive liberal arts college, is the tail-end Charlie at 60.

At Sarah Lawrence College, in Bronxville, N.Y., graduates often choose careers in education, public administration or social work, and come out earning, on average, just $38,600 after two years. (Officials at Sarah Lawrence say that figure may underestimate alumni salaries but also contend that’s beside the point: “Their rewards are measured not just by earnings but by how much they are giving back to society,” says Tom Blum, the vice president of administration.)

Smart Money analyzed only 50 colleges and universities: the eight Ivies, plus more than 40 of the priciest non-Ivy private schools and public universities (based on out-of-state tuition).

As Cost of College points out, the SmartMoney rankings assume students pay the full cost. Many students get some financial aid, especially at the elite private colleges, which have huge endowments. And public flagship universities are a very good deal for in-state students.