The Dow Jones Industrial Average staged its best two-week performance since the 1930s, a dramatic rebound that has left many investors with a confounding reality: soaring share prices and a floundering economy.

The explosive rally is a sign that many are positioning for the U.S. to make a speedy recovery when the coronavirus crisis eases. Investors have been encouraged in recent days by signs that several states will move to resume business, along with hopes that a viable treatment for Covid-19 could be near.

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