WASHINGTON — It’s not too much of an exaggeration to say the US economy was powered by car sales in 2012. Auto companies are now expected to have sold 14.5 million new vehicles in 2012, according to Kelley Blue Book. That’s a 13 percent rise over last year and the highest number of sales since the financial crisis hit.

If cars hadn’t been flying out of dealerships, the year would have looked considerably bleaker. Vehicle purchases by consumers alone accounted for roughly 30 percent of all economic growth in the first half of the year, according to Credit Suisse.