In selecting the family income categories, consideration was given to which students received Pell grants and subsidized Stafford loans. The Pell Grant program targets students from low-income families. At a family income level of $25,000–29,999, two-thirds of students at public 4-year institutions received a Pell grant in 1999–2000). At the next highest income level, the percentage dropped to below half (46 percent). Thus, $29,999 seemed to be an appropriate upper bound for the low-income category. In defining the middle-income category, the goal was to identify students who were not served by the Pell grant program but who used federally subsidized loans to help pay for college. The lower bound for this group appears to start at about $45,000. Above $45,000, only 3 percent of students at public 4-year institutions received Pell grants of $1,000 or more. The upper bound of the middle-income category was set at $74,999, beyond which fewer than one-quarter used subsidized Stafford loans to attend a public 4-year institution. This categorization of low- and middle-income students left a low-middle-income group that was not clearly one either low- or middle-income ($30,000–44,999). At the higher income levels, a distinction was made between upper-middle-income ($75,000–99,999) and high-income students (more than $100,000) because of the difference in the rates at which the two groups received subsidized loans at private not-for-profit institutions (33 percent for the former and 18 percent for the latter).