Work-search log: how detailed does it need to be? - 13 months and counting

I have been applying to about 16 jobs a week as a retail manager, but I am unsure what my state wants in the log. Any experience at all would help. I also did a résumé workshop at the library. What do you record?

I was asked for my log once, after six months. Having it in a spreadsheet made it painless.