- 1963 to 196411,534
- 1965 to 196915,929
- 1970 to 197410,032
- 1975 to 19799,668
- 1980 to 19846,809
- 1985 to 19898,672
- 1990 to 19945,131
- 19952,246
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