Carvana (CVNA) stock tumbled on Thursday after the company posted mixed results for its fourth quarter, with revenue jumping but profits missing estimates. The e-commerce used car dealer posted revenue of $5.60 billion versus $5.27 billion estimated per Bloomberg, up 58% compared to a year ago. Carvana said retail units sold hit 163,522 compared with 157,226 estimated, a jump of 58%. But Carvana reported adjusted EBITDA (earnings before interest, taxes, depreciation, and amortization) of $511 million v ...