- 1890 to 18992
- 1900 to 19099
- 1910 to 1919153
- 1920 to 1929745
- 1930 to 19391,221
- 1940 to 19491,739
- 1950 to 1959967
- 1960 to 19691,786
- 1970 to 1979889
- 1980 to 19891,066
- 1990 to 199944
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