What a Crappy Investment

According to CNN:

LONDON, England — A 1,200-year-old Anglo-Saxon penny has sold for �230,000 ($409,000), setting what the auction house said was a new world record for the most expensive British coin.

Curious, I put in a penny in a compound interest calculator at an APR of 3% for 1,200 years, which I thought would be fairly conservative for the range of time. The result?

That original penny, had it been invested, would be worth $25,390,406,045,714.81, which is considerably more than the net worth of the planet as near as I can tell. $25,390,406,045,714.81 is slightly more than $409,000.