- 1900 to 19092
- 1910 to 1919343
- 1920 to 19291,539
- 1930 to 19393,039
- 1940 to 19493,309
- 1950 to 1959699
- 1960 to 19690
- 1970 to 19790
- 1980 to 19891
- 1990 to 19961
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