Trying to make a counter for Powerpoint

Hey guys, I need some help with VBA in terms of getting some stuff done for a presentation I'm making for powerpoint.

You see, I'm making a game show for a convention I'm going to in a few months, and I pretty much have it all nailed down. The only thing I need is a counter that is displayed at the top of the slide that I am presenting. I need it to go up in increments of $25 every time I click on each blue box (see attached picture)

As you can see, it's fairly simple, it's a quick game where I give out a list question (ex: Name an MLB baseball team), and each person has to give a correct response. If someone duplicates an answer or can't think of an answer, the next person can knock them out by giving their own correct answer. All I need is the counter to make a money amount go up every time someone gives a correct response.

Can someone help me with this? Thanks.