Guess How Much

So for the past year I've been saving up all the one yen and five yen coins that have accumulated in my pockets.  They're the equivalent of one and two pence pieces, except even more useless if you can imagine such a thing.

As you can see there are a couple of 100 yen coins in there, but they'll be gone by the time I take it to the post office.

Anyway, here's the question, how much money is in there?