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system
what type of returns vanguard is quoting?
user
from the vanguard page -  this seemed the easiest one as s&p data is simple to find. i use moneychimp to get -  which confirms that vanguard's page is offering cagr, not arithmetic average. note: vanguard states "for u.s. stock market returns, we use the standard & poor's 90 from 1926 through march 3, 1957," while the chimp uses data from nobel prize winner, robert shiller's site.
assistant