This paper examines factors that affect four-year graduation rates at public colleges and universities in the United States. The author uses econometric modeling and regression analysis on data from 199 randomly selected public institutions. Key findings from the study suggest higher freshman retention rates, average financial aid amounts, smaller class sizes, in-state tuition costs, and average incoming GPA positively impact graduation rates, while higher male percentages, urban locations, and Hispanic percentages have negative effects. Percentages of Greek life members did not significantly impact rates.