- 1908 to 19092,506
- 1910 to 19112,588
- 1912 to 19132,679
- 1914 to 19152,698
- 1916 to 19173,966
- 1918 to 19195,165
- 1920 to 19213,367
- 1922 to 19233,301
- 19242,558
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