- 1974 to 1974 5,637
- 1975 to 1976 6,321
- 1977 to 1979 7,996
- 1980 to 1981 3,308
- 1982 to 1984 4,240
- 1985 to 1986 4,855
- 1987 to 1989 4,399
- 1990 to 1991 1,700
- 1992 to 1994 2,350
- 1995 to 1996 2,607
- 1997 to 1997 1,256
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