Planet Money: Why The Price of Coke Didn't Change For 70 years

From Planet Money:
Prices go up. Occasionally, prices go down. But for 70 years, the price of a bottle of Coca-Cola didn't change. From 1886 until the late 1950s, a bottle of coke cost just a nickel.

On today's show, we find out why. The answer includes a half a million vending machines, a 7.5 cent coin, and a company president who just wanted to get a couple of lawyers out of his office