Both graduates from four-year colleges and those who did not attend college believe that, on average, a bachelor's degree makes a difference of $20,000 in yearly earnings, according to a 2011 Pew Research Center survey on whether college is worth the cost. U.S. Census Bureau data shows these estimates are pretty accurate--the median earning gap between a high school grad and a college grad in 2010 was $19,500.
The Bureau of Labor Statistics confirms that college pays off, reporting that as the level of education increases, earnings increase and the unemployment rate decreases. Workers with high school diplomas earned 2010 median weekly wages of $626. Those with associate degrees earned 22 percent more; bachelor's degree holders netted 66 percent more; and workers with master's degrees earned more than twice as much as those with high school diplomas.