- 1950 to 19517,328
- 1952 to 19536,503
- 1954 to 19555,914
- 1956 to 19575,911
- 1958 to 19595,881
- 1960 to 19618,822
- 1962 to 19639,937
- 1964 to 196511,871
- 1966 to 196710,491
- 19688,227
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