Edmunds used to recommend consumers spend no more than 15 percent of take-home pay on a new-vehicle payment.
But the concept of affordability is more complex these days, said Jessica Caldwell, executive director of insights for Edmunds, an industry data analysis firm owned by used-car retailer CarMax. Caldwell told Automotive News she couldn't provide a new rule of thumb.
"There's so many variables, it's hard to stick an exact number on it," Caldwell said.