What is the relationship between an institution's economic diversity and graduation outcomes for low-income students? How does this relationship vary by institutional selectivity? The graph below displays the relationship between an institution's economic diversity (measured as the percentage of undergraduate students who receive a Federal Pell Grant) and six-year bachelor's degree completion rates for Pell Grant recipients. Generally, as the share of low-income students increases, the six-year bachelor's degree completion rate decreases (as evidenced by the downward slope). Overlaid in color is the institutional selectivity (measured by Barron's Admissions Competitiveness Index). The vertical position of the colored dots and lines, particularly within the higher selectivity categories, shows the economic stratification at U.S. four-year colleges. The most selective institutions typically serve fewer low-income students relative to their undergraduate enrollments, but those who are able to gain admission exhibit exceptionally high completion rates.