Looking for a new car under $20,000? Good luck. Your choice has dwindled to just one vehicle

At a time when Americans increasingly want pricey SUVs and trucks rather than small cars, the Mirage remains the lone new vehicle whose average sale price is under 20 grand — a figure that once marked a kind of unofficial threshold of affordability. With prices — new and used — having soared since the pandemic, $20,000 is...