In the United States, the annual salary of someone without a college degree is (on average) $28,039, whereas the annual salary of someone with a college degree is (on average) $50,983. If the cost of a four-year public university is (on average) $12,369 per year, how many months would it take for the investment in a college degree to be paid for by the extra money that will be earned with this degree?

Round your answer to the nearest month.

Note: You should not assume anything that is not in the problem. The calculations start as both enter the job market at the same time.