- 1950 to 19517,488
- 1952 to 19536,662
- 1954 to 19556,073
- 1956 to 19576,074
- 1958 to 19596,048
- 1960 to 19619,060
- 1962 to 196310,173
- 1964 to 196512,121
- 1966 to 196710,749
- 19688,474
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