How do you calculate this ERA?

ERA formula (ER x 9)/Innings pitched

In your case it is (2 x 9)/0 so the answer is Infinity.

Not good

Well I can't put infinity into the book, so there must be a way to calculate it not only for that game, but also for the overall season statistics. Obviously you can just add the two runs to the overall innings pitched over the season, but how is it calculated for that one game?

Luv has it right, for the game its infinity.

Some reports will show it as INF. I've seen 99.999 or some other big number.

I have a spread sheet for both of my children that does calculations by game and by season. There are some games were ERA was #DIV/0!

Why can't you put infinity in the book?

I'm wondering why anyone is worried about ERA for 1 game.

I think it's the same as putt-putt. The max is 8.

If it's a manual book I'd put the old lazy 8. Not up to speed on the electronic stuff but if they know anything about baseball this happens and they should have accounted for it.