I have a worksheet for our employees to figure 401(k) contributions and matches that's unique to our company. In my worksheet I included a drop down menu that allows then to figure the effect of their contribution as a percentage of salary or as a flat dollar amount. They choose from the drop down option and depending on their choosing a percentage or flat dollar amount they enter it in an empty cell below. Is there a way to have the number format change to either currency (for the flat dollar amount) or percentage based on what they chose from the drop down?

Everything I see in conditional formatting relates to changing the cells color. I have tried to figure out a way of using an if statement to do this, but cannot figure that out.