Simplified Investing

Last week in Bologna I met an investment banker and we got on the topic of ING Direct and their incredible success with a strategy centered around simplicity. The banker told me something interesting I hadn't heard before that I couldn't find online. Something to the effect that ING Direct tells their customers that to determine how much of their money they should put into high-risk investments versus low-risk ones, just take your age up to 100 years old. However old you are, that is the percentage that you should invest in the low-risk stuff; then take the number 100 and subtract your age from it and invest that percentage in the high-risk stuff. I was impressed with the simple elegance of the thought.