Public colleges with the best bang for your buck

college roi south dakota school of mines technology

20-year return on investment : $717,700
Annualized return: 13.4%
Total 4-year cost of attendance: $82,100

The South Dakota School of Mines and Technology fell a couple of places in PayScale's rankings since last year, but it remains one of the best public schools for return on investment.

Like most of the other schools topping the list, this Rapid City-based school focuses on science and engineering fields.

According to PayScale, a full 92% of the school's 2,300 students are in STEM fields, and graduating students tend to earn about $67,000 at the beginning of their careers.

PayScale's Frank noted that although geological scientists and petroleum engineers are currently very highly-paid professions, the recent fall in oil prices that is impacting the industry may knock some schools down a few places in next year's list.

First published March 5, 2015: 1:50 PM ET

Source: PayScale
Based on employee survey data, PayScale calculated total median pay for a school's undergraduate alumni over a 20-year period and compared it to the median pay for a high school graduate over 24 years. The return on investment (ROI) in 2014 dollars was determined by taking the difference between those median pay figures and subtracting the in-state cost of attending the school in 2014 -- including tuition, room and board, and other costs -- and adjusting for scholarships and grants. The annualized ROI is calculated by dividing the earnings differential by the total cost and represents the percent of expected ROI received each year after graduation. Unlike in previous PayScale reports, the earnings differentials in this report do not take into account graduation rates. Alumni who attended graduate school or other higher education were excluded.

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