Question about flush draw outs

This is probably a dumb question, but if you're on a flush draw, is counting 9 outs for that draw something that really makes sense? Because that really assumes that no one else in the game was dealt a card of that suit. Wouldn't it make more sense to find the EV of the amount of, say, clubs left in the deck, and use that?

Say there are 6 people. I have two clubs and two are on board. Should I take outs to be 9 - (Expected # of clubs in 10 cards dealt)?