- 1851 to 18541,317
- 1855 to 18591,496
- 1860 to 18643,255
- 1865 to 18692,596
- 1870 to 18741,927
- 1875 to 18791,772
- 1880 to 18841,777
- 1885 to 18892,450
- 1890 to 18943,205
- 1895 to 18992,819
- 1900 to 19043,152
- 1905 to 19093,016
- 1910 to 19143,585
- 19152,323
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