- 1945 to 19465,478
- 1947 to 19498,377
- 1950 to 19517,525
- 1952 to 19547,671
- 1955 to 19565,943
- 1957 to 19596,983
- 1960 to 19619,082
- 1962 to 196412,780
- 1965 to 196611,360
- 1967 to 196912,361
- 19707,094
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