- 1968 to 1969 10,263
- 1970 to 1974 9,526
- 1975 to 1979 9,238
- 1980 to 1984 6,508
- 1985 to 1989 8,389
- 1990 to 1994 3,664
- 1995 to 1997 3,474
The preservation of the Duke University Libraries Digital Collections and the Duke Digital Repository programs are supported in part by the Lowell and Eileen Aptman Digital Preservation Fund