Can you make COUNTA ignore cells or words?

I'm sorting people in buildings and using COUNTA to keep track of the amount of people, then that just goes to a SUM. I want to remove people temporarily, and not have them in the COUNTA. I don't want to remove all the names then type them all over again. Is COUNTA the best option for this? or is their a way to comment out word or cells temporarily?

Thanks