re: What is the ratio of the price you paid for your car to your annual salary?

Most financial guru's recommend buying a quality used car for cash, and then driving it until the wheels fall off.

You can't do that with the 1/10th rule. Most people would be buying something that may need a lot of maintenance in the near future, or even replaced.

The fact of the mater is that cars aren't bought by most people with cash in hand. They are financed, and therefore you may want to keep your annual payment total to less than 10% of your gross income.