- 1960 to 19618,828
- 1962 to 196412,517
- 1965 to 196611,090
- 1967 to 196912,070
- 1970 to 19717,717
- 1972 to 19747,548
- 1975 to 19766,655
- 1977 to 19798,336
- 1980 to 19813,543
- 1982 to 19844,513
- 1985 to 19865,097
- 1987 to 19884,013
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