proportional editing shortcut

I like to use a wacom tablet when I work. Is there a keyboard shortcut when you are using proportional editing to shrink the area it affects? If I was using a mouse, I’d use the mousewheel, but my stylus does not have a wheel. I’ve tried the + and - keys on the keyboard and number pad (they don’t change it).

Page up / Page down

Thanks!

Do you know if there are keyboard shortcuts for the brush size when you are in Sculpt mode?