- 1945 to 19464,473
- 1947 to 19497,410
- 1950 to 19516,708
- 1952 to 19546,861
- 1955 to 19565,134
- 1957 to 19596,150
- 1960 to 19618,395
- 1962 to 196412,079
- 1965 to 196610,707
- 1967 to 196911,716
- 19706,665
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