|# of files||# of deposits||File format|
The usual suspects appear in the usual volumes: lots of SPSS, PDF, and MS Word. There seems to be a lot of dBase in this month's report: that is unusual, and is worth investigating. The service that generates MIME type works pretty well most of the time, but is not 100% error-free. And to that point, I suspect that the purported video files and C++ source code are actually something else.
The two deposits with many "unknown" (application/octet-stream) are worth a look too. They may be some esoteric format that we do not see all that often.