- 1851 to 18541,320
- 1855 to 18591,499
- 1860 to 18643,259
- 1865 to 18692,600
- 1870 to 18741,931
- 1875 to 18791,776
- 1880 to 18841,781
- 1885 to 18892,454
- 1890 to 18943,208
- 1895 to 18992,822
- 1900 to 19043,156
- 1905 to 19093,019
- 1910 to 19143,587
- 19152,325
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