With 44.5 million student loans in the U.S., it's becoming ever more important for students to get the highest return possible on their higher education "investment."

In a new ranking, WalletHub grades U.S. colleges and universities on a number of factors, including how successful they are at putting graduating students on the road to a career that will enable them to pay off their debts and be financially successful.

In 2017-18, a public four-year college costs $25,290 a year for in-state residents, while a private four-year college cost double that at $50,900, according to lendedu.com.

The "career outcomes" section of the WalletHub ranking looks at the ratio of starting salaries among graduates compared to the cost of education. The ranking also considers each school's graduates in terms of their student loan default rates, their success at reducing debt and how many of them are outearning people with only a high school diploma. WalletHub also compared colleges on how much their graduates were earning 10 years after graduation.

These are the colleges, in ascending order, that topped the WalletHub career outcomes ranking:

10. Harvey Mudd College

The Claremont, Calif., liberal arts college has one of the highest graduation rates in the ranking at 90 percent. Graduates have the second-highest return on their educational investment with a reported average early career salary of $85,600, according to payscale.com.