The term, when used to describe stocks, refers to changes in investor sentiment
When Wall Street analysts use the terms “rerating,” “rerate” or “derating,” they are talking about something at the heart of the investing process: changes in investor sentiment.
“When a stock sees a rerating, people are either more excited or less excited about the stock,” says Jason Brady, chief executive of Santa Fe, N.M.-based asset-management firm Thornburg Investment Management. An out-of-favor stock or sector that sees an increase in investor interest, for example, is said to be rerated.
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