Nothing ever tracks anything precisely, but that doesn't matter. All accounting involves approximations. I have millions in index funds and related ETFs. Do you think the Book Value of a company is precise to the cent??? Numbers like Depreciation are simply best guesses. Buffett and Munger often talked about the Margin of Error.
If you own stock in a car rental company, do you think those cars could be liquidated precisely at book value??? And even the most accurate numbers are updated every three months and released to the public only much later.
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