Using the rule of 72 and a 3.5% US inflation rate, it would take 20 years for the cost of something to double.

The cost of something over 40 years going from 400-4000 dollars is because of Credit Cards fucking up the entire Supply/Demand curve.

EDIT: Rule of 72 is an easy way to see how long it takes money to double at a given interest rate. Divide 72 by the interest rate to get the years needed. So an investment earning 9% interest will double your money every 8 years. Useful information.

sounds to me like
step 1:buy hershey bars
step2: ?
step3: profit

who would buy a chocolate bar that is 50 years old? most people dont buy chocolate bars if they are 50 days old

Ouch. That's expensive. I would drink nothing but quality beer if the prices were that close. I see no other reason to drink Budweiser, except it is cheap.

I am pretty sure these prices are BEFORE tax. Maybe not, but it would make more sense that way.