DublinPole is absolutely right about BUD-KRK. Budapest airport publishes monthly data here:
http://www.bud.hu/english/business-a...ines-9082.html
The average flown loads on BUD-KRK from February to October have been 36%, 48%, 54%, 50%, 44%, 36%, 37%, 37%, 44%. It's only a short hop, but with such low loads, Ryanair would need very decent yields in order for the route to be profitable.
I can also confirm OltonPete's figures for BHX-BUD. Loads certainly haven't been a problem on that route.