Stocks have not been this attractive vs bonds since the 1950s, according to Bank of America

A worker is seen on the floor of the New York Stock Exchange (NYSE) in New York, U.S., February 28, 2020.
Brendan McDermid | Reuters

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The cascading decline in stocks over the last one month, along with plunging yields, have brought equity valuations down to cheap levels relative to bonds rarely seen in history, according to Bank of America.