Carvana Co (NYSE:CVNA) shares are trading lower due to a downgrade from JPMorgan analyst Rajat Gupta, who cited valuation concerns. Gupta downgraded Carvana from a Neutral rating to an Underweight rating and set a $10 price target. The analyst firm also suggested that Carvana should consider a debt/equity exchange. This comes after Carvana shares rallied nearly 50% over the last month and more than 700% since the start of the year.