- 1950 to 19517,329
- 1952 to 19536,504
- 1954 to 19555,915
- 1956 to 19575,912
- 1958 to 19595,882
- 1960 to 19618,828
- 1962 to 19639,942
- 1964 to 196511,878
- 1966 to 196710,494
- 19688,230
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