Doesn't make sense. We do this for investment return projections. We really need to be doing the same for inflation too!
Ed McQuarrie talks the REAL History of Stocks and Bond performance.
https://www.morningstar.com/funds/most-stunning-fact-about-vanguards-etf-flows-2
This article shows people are pulling money out of mutual funds and putting it into index funds an example is VOO. Also Vanguard Primecap and Core fund opened the fund due to them both because of money being pulled out. INDEX ETF's way to go tax efficient and low expenses