Rats Not Adding Up?

I know medals are relatively meaningless at this point in the game, but getting a new one is a nice treat that keeps the game interesting for me in between the 'dex additions.

I almost have my gold tiny Rattata medal, but all of my XS catches are not adding to the total. After I noticed, I started saving the XSs as proof (at least to myself); I caught 5 and total only increased by 2. Anyone else notice this with Rats or any other critter medals?