| Class | Type of work | January - June 1951 | July - December 1951 |
| A | Books (from part 1A) | 1,393 | ??? |
| A, B | Contributions to Periodicals | 418 | 247 |
| B | Periodicals | ??? | ??? |
| D | Dramas | ??? | ??? |
| G | Works of art | 4 | 22 |
| H | Reproductions of works of art | - | - |
| I | Scientific and technical drawings | 0 | 26 |
| J | Photographic works | 11 | 12 |
| K | Prints and pictorial illustrations | 97 | 26 |
Categories not represented in the table above (or in the online collection for 1951) include: lectures and other works prepared for oral delivery, maps, commercial prints and labels, motion pictures, and music.
Table above based on tables in issues of the Catalog of Copyright Entries, 1951.