- 1945 to 1946 4,236
- 1947 to 1949 7,258
- 1950 to 1951 6,668
- 1952 to 1954 6,819
- 1955 to 1956 5,097
- 1957 to 1959 6,104
- 1960 to 1961 8,351
- 1962 to 1964 12,028
- 1965 to 1966 10,663
- 1967 to 1969 11,661
- 1970 to 1970 6,619
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