Silence_Dogood

Hey, I deleted that last message because the math was wrong. Here's the correct math, I verified it with a friend who's a physics professor:

e^r/(e^r-1) = ye^ry

This tells us what year y has a total interest which equals the required principle for 1 year's interest yield to equal our annual deposit. All rates are linear, so this is obviously an estimate.

The equation is impossible to solve algebraically, but if you plug it into a calculator in this form:
0 = ye^ry - e^r/(e^r-1)
plugging 0 in for y, and y (years) for x

y = xe^(rx) - e^r/(e^r-1)

and find the x intercept, you will find the year's required for any given interest rate r.

For 8% interest, y is 7.27 years. This is an extremely conservative interest rates if you're interested in the stock market. This would be equivalent to a 4% inflation, and 4% yield (low). One stock I'm investing in is giving me 28.5% interest in writing calls alone, that's not including capital gains (the price of the stock rising), inflation, and dividends. Including capital gains and inflation, because this stock doesn't have dividends, my rate for this stock (erts:nasdaq) is 63.75%. Plugging into this function my y is a staggering 1.07 years.

Investing is the only thing that seperates the rich from the poor.

Hi Silence_Dogood!
You may wish that we exchange ideas. my email: idrisomeiza@yahoo.com