The economics profession has a problem with what it does and does not measure and report.
Cars wear out. That is PHYSICS. It makes no difference whether the car is a Capital good or a Consumer good. But as far as our economists are concerned ONLY CAPITAL GOODS DEPRECIATE.
They hardly ever talk about the Net Domestic Product. We are running a world of 7 billion people on defective algebra. We are supposed to believe that no economists have noticed this in 60 years?.
http://www.toxicdrums.com/economic-wargames-by-dal-timgar.html