DETROIT (AP) — Shares of upstart used-vehicle chain Carvana have tumbled further due to the company’s struggles with falling prices and waning demand for its products. Monday’s 16% drop comes after the shares fell almost 40% on Friday after Morgan Stanley analyst Adam Jonas suspended his rating and price target for the company. Carvana reported a $283 million third-quarter net loss on Thursday. It had been growing quickly as used car prices soared after the pandemic. But it has been caught in an environment where rising interest rates and high prices have sent many potential used-car buyers to the sidelines.