What exactly does the "Drop-In Space" number on my calendar mean?

Does this mean the number of drop-in clients I can take, or does it mean the number of drop-in spaces per client?

I meant to indicate in my schedule that I can do 3 drop-ins per client per day per stay, but if that actually means I can take on 3 drop-in clients at a time, that would mean 9 total drop-ins per day, which is more than my schedule can handle! Please advise.