Either way, it's not too bad. A shame that he hasn't played more, but football is cruel at times.
Look at the diagram in Unhappy's link showing the games and wether Mata played. (X marks if not played). He had 3 games end Sept beginning of October and then a run of 4 games in December. The rest is a bit hit and miss.
In between that he had a 24 day spell with out football in Aug/Sep and another 22 day spell Nov/Dec with out any football. I think the point we're trying to make is that he was bit part this season and that can make if difficult for any player to find any sort of form.
Anyway, we might be getting a bit too technical here. Here's hoping he can find some form and guide United to 6th come May.