This is a great study on this subject, although the data is getting a little old by now (1993 study with 1979 high school students). http://www.irs.princeton.e

This is a great study on this subject, although the data is getting a little old by now (1993 study with 1979 high school students). http://www.irs.princeton.edu/pubs/pdfs/311.pdf http://www.irs.princeton.edu/pubs/pdfs/311.pdf Quote of interest: "We generally continue to find positive and significant coefficients on numbers of credits completed, as each year's worth of credits was associated with a 3-5% increase in both hourly wages and annual earnings. Perhaps surprisingly, the estimated 'sheepskin effects' of degree completion over and above the value of the credits completed were often small when studying wages and earnings."