(Bloomberg) -- Valuations in the Standard & Poor’s 500 Index increased by the most since the financial crisis last year as 460 stocks rose, more than any year since at least 1990. Neither are reasons to bet against equities now.

While Wall Street strategists are the most cautious in almost a decade after the broadest U.S. rally on record sent price-earnings ratios up 19%, expanding multiples have preceded advances twice as often as they have retreats, data compiled by Bloomberg show. Since 1936, the S&P 500 has risen 69% of the time following quarters when valuations widened, the data show. The average return is 14% in years after more than 400 constituents climbed, according to data compiled by Strategas Research Partners.

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