Which Degrees Offer the Best Return on Investment?

With the average cost of a bachelor's degree now running about $68,500 at State U. and $154,300 at a private college, one might well wonder if the investment is worthwhile. In short, it is. But the return very much depends on your major. "What you make pretty much depends on what you take," says Anthony Carnevale, director of the Georgetown University Center on Education and the Workforce.

Yes, of course you want to follow your passion. But if you were to coldly calculate which direction would be most fruitful, where would you land? Probably doing what Cathy Coussons does, trying to assess the best ways to coax oil from the ground. The reservoir engineer at Marathon Oil Corp. in Houston earned a bachelor's of science in petroleum engineering at the University of Texas-Austin in 2011. "We get paid well, travel, work with good people, and get good benefits," says Coussons.

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Indeed, after analyzing the earnings associated with 171 bachelor's level degrees, Georgetown researchers found that petroleum engineers as a group fetch the highest median salary: $120,000. Why? "It's difficult and there aren't that many," says Lawrence Jacobson, executive director of the National Society of Professional Engineers.

In fact, engineering dominates the list of majors with the highest earnings. Only two non-engineering degrees show up in the Top 10: pharmacy/pharmaceutical sciences and administration ($105,000) and the combo degree of math and computer sciences ($98,000). Grads in relatively low-paying (but fast-growing) early childhood education, by contrast, pull in a median of $36,000.

The problem-solving capabilities of engineers and computer scientists put them in demand across the economy. People in the STEM disciplines--science, technology, engineering, and math--are hot properties for their proficiency in "the core language of technology and commerce in the world," Carnevale says. "Engineering is the new liberal arts degree--it prepares you for a lot."

And those strong in math can earn more in healthcare, business, finance, economics, and accounting than in some traditional STEM occupations, he says. "Math skills and quantitative skills drive operations."

When it comes to job prospects for recent grads, too, a survey by the National Association of Colleges and Employers shows that newly minted engineers have been the most heavily recruited and highest paid in the class of 2012, with a median starting salary of $58,581. That's followed by computer scientists at $56,383. Economics majors are pulling in nearly $55,000; business majors, just under $48,000.

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The low end. At the other end of the spectrum, the Georgetown study, based on the Census Bureau's 2009 American Community Survey, found that people who say they got an undergraduate counseling psychology degree are the lowest paid, at a median of $29,000.

But some experts believe that stat may be based on faulty self-reporting, since counseling psychology is overwhelmingly an advanced degree. Indeed, most college students majoring in psychology get general psych degrees, says Cynthia Belar, executive director of the American Psychological Association. And those now boast a median income of $45,000. An advanced degree adds at least 45 percent.

In fact, historically it's been the case pretty much across the board that the more education you have, the more you're likely to earn. But again, field of study matters; that old rule of thumb is "less and less true," Carnevale says.

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Nearly 30 percent of people with an associate degree now earn more than the median salary of workers with a bachelor's, while 40 percent of those with a bachelor's out-earn people with a master's. Engineers with a four-year degree, for instance, tend to make more than people with advanced degrees in education. In some fields, pursuing an advanced degree makes a big difference, of course; molecular biologists can typically increase their pay by 115 percent. Conversely, petroleum engineers get a bump of just 7 percent.

Salary doesn't tell the whole story, to be sure. "I love my job," says Philadelphia preschool and Head Start teacher Theresa Mettee, who earned her degree in 2007 and makes $36,500. The work makes her feel valued, she says. With the support of her employer, Mettee is working on the credits required to become state certified, which will get her almost to a master's degree--and boost her pay by $10,000.

Here are the undergradate majors that offer the highest and lowerst median pay, according to the Georgetown University Center on Education and the Workforce.

Highest median pay:

Petroleum engineering: $120,000

Pharmacy/pharmaceutical sciences and administration: $105,000

Math and computer sciences: $98,000

Aerospace engineering: $87,000

Chemical engineering: $86,000

Lowest median pay:

Counseling psychology*: $29,000

Early childhood education: $36,000

Theology and religious vocations: $38,000

Human services and community organizations: $38,000

Social work: $39,000

*Overwhelmingly a graduate degree.