By default, these expressions are purely visual. But you could attach a faster tempo to the expression (via the Playback thumbnail -> Type -> Tempo). Try a 150 % value (quarter note = 90 instead of 60 for instance).

Stephen did you understand what Michel Herr was saying? I would like to add this as well. There is a function in the Expression tool that allows you to assign a tempo change to anything including rehearsal letters. Just as an example I created some random expressions, one being a tempo Q=75

Edit that in expression tools. Sorry they won't let me upload any pictures. But once you click on edit click on your playback tab. You will see a host of things you can do, one including tempo. Choose your dotted quarter note and add the value where you see value. 

Place that expression at the measure you want the tempo to change. Works every time.

My tempo changes at that point and Tempo has another tempo assigned to it, which also changes at letter A. 

In the newer version of Finale there is already a Q=120 in parenthesis that you can edit and it will automatically change to the tempo you indicate. Try both. 

Hi, Michel and Ronnie!

Thank you both so much for your tips.  Ronnie, I followed the steps you laid out above and it worked.  I really appreciate the help!

Thanks again,

Stephen