- 1876 to 18791,546
- 1880 to 18841,800
- 1885 to 18892,474
- 1890 to 18943,242
- 1895 to 18993,324
- 1900 to 19043,482
- 19052,334
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