Question Resizing a Progress Bar

This seems like a really stupid question, but how do you resize one of the built-in progress bar controls?
None of the size properties seems to do anything at all to it. I can drag the blue square or manually change the size values, nothing changes once I click "Run". This is just the plain, basic progress bar that's on the Controls box, not modified by scripts or anything else.

 

Thanks! I'll check it out!