And with Americans now holding a record share of their wealth in equities, economists are warning of a possible downshift in returns ahead.His remark echoes a growing unease among market watchers: valuations across multiple asset classes have swelled after years of easy money and resilient investor appetite. Federal Reserve chair Jerome Powell recently cautioned that stock prices “are fairly highly valued (4).”“Asset prices are kind of high,” Dimon added. “In the back of my mind, that cuts across almost eve ...