College grads typically earn more than workers with high school diplomas, but just how much varies from job to job. Earning a bachelor's degree is statistically a huge payoff in many professions, but for some, such as electricians, janitors and postal service mail carriers, there's no difference between the lifetime earnings of college and high school grads, according to research from Georgetown University's Center on Education and the Workforce. In fact, workers with bachelor's degrees in jobs such as carpentry actually have a lower median wage than those without.

Read on to discover the jobs where the difference between a bachelor's degree and a high school diploma is at least seven figures over a lifetime. Culled from Georgetown's The College Payoff study, these jobs don't absolutely require a four-year degree to break in, but they do provide substantial financial incentive for those who hit the books.