Before looking it up, please imagine a low cost index ETF and its expense ratio. As an example, VOO says it is %0.03 .
Now, the thought experiment: how many stocks in the ETF portfolio have EQUAL OR LESS presence in the portfolio; in other words, you buy less of those stocks than you pay in expenses.
You probably by default think 0 .. on being asked are uncomfortably thinking more than 0. What is your guess, and have you taken the time to look it up?