Artist Name and Album Name in "Album" Field


I have looked all over Google and the FAQs for the answer to this so I hope it hasn't been asked before.

I have a load of songs which have empty "artist" fields but the "album" field contains the artist name followed by a dash followed by the album name.

I would like to take the artist name from the "album" field and insert it into the "artist" field and leave the album name in the "album" field.

E.g This is what I have now
Title: "Exodus"
Artist: (blank)
Album: "Bob Marley - Legend"

And I would like to have
Title: "Exodus"
Artist: "Bob Marley"
Album: "Legend"

Please can someone tell me the appropriate action I need to do? I have this format for several hundred albums so I have to find a solution this way!

Thank you very much!

I think the following Guess Values action should work. Be sure to test it first on a few tracks.

Action type: Guess values
Source format: %album%
Guessing pattern: %artist% - %album%

Thank you very much, this solution worked perfectly. Much appreciated!