- 1950 to 19516,707
- 1952 to 19535,896
- 1954 to 19555,308
- 1956 to 19575,281
- 1958 to 19595,266
- 1960 to 19618,395
- 1962 to 19639,512
- 1964 to 196511,441
- 1966 to 196710,127
- 19687,880
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