Can you grab across multiple files and compare?

In this example I'm tagging work/movement etc. movementtotal would be the issue here. Wondering if I can somehow take this aggregate data, count the occurrences of each work and then use this to populate movementtotal in an action.

Thanks.

You can only do it partly by hand.
Sort for the works, mark the equal works and apply an action:

Type: Format Value
Field: %movementtotal%
Format String: %_total_files%

If you want to do it without sorting and marking by hand you would have to make an export-file and later import from this export-file.