Any academic institution reported as receiving Federal S&E support in the annual Survey of Federal Science and Engineering Support to Universities, Colleges, and Nonprofit Institutions during the 19712000 period is included in this study. To the extent possible, duplicate institutions were combined into one institution to prevent double counting. For descriptive purposes, all institutions have been assigned to their 1994 Carnegie classification. If an institution was not classified in 1994, either because it did not fit into one of the Carnegie classes or because it did not exist at that time, it was included in other. A number of institutions, particularly 2-year institutions, did not exist for at least part of the period prior to 1994 and some may have closed or merged after 1994. Table 244 in the National Center for Education Statistics' Digest of Education Statistics: 2001 indicates that the number of 2-year institutions may have increased by more than 30 percent between 1971 and 2000. For comparison purposes, the number of institutions listed in each of the Carnegie categories is generally the number reported by Carnegie in that category in 1994. The numbers of institutions in the groups that are the main recipients of Federal S&E supportthe research, doctorate-granting, and freestanding medical institutionsprobably have not varied much, if at all, during the 30-year period.