لمن لم يقرأ المقال عن المعادلة السحرية لقراهام ها نحن نضعها هنا للإطلاع:
In The Intelligent Investor, Graham laid out an equation that was designed to help people value a growth company. The equation goes like this:
P = ProjEPS * (8.5 + (2*G)) * (4.4/AAA yield)
Looks scary, but it's not. Let me break it down for you.
P = the price of the company's stock. This is what the equation will tell you.
ProjEPS = the projected earnings per share. You're looking for next year's estimated earnings per share. (Get estimates here.)
8.5
Graham surmised that a zero growth stock should have a P/E multiple of 8.5. This reflects an average return of 12% per year. For what it's worth, I think this is a little shaky given the wide variety of circumstances leading to a company with zero growth. As you'll see, Graham put some qualifiers on this equation.
2*G
G is the long-term projected growth rate of a company's EPS. Graham said that you should be comfortable that the company will grow its earnings at this rate over the next seven to 10 years. Unfortunately, most companies/analysts only give 5-year expected growth rates, so you'll have to use those.
4.4
This was Graham's benchmark for a required rate of return to invest, period. He surmised that at a minimum, an investor needed to be compensated for the effects of inflation and a small risk premium above that. You might be tempted to "play around" with the 4.4, but I keep it constant.
AAA yield
This is the yield on the AAA corporate bonds. I like to use the 30-year composite yields, but they are difficult to find. Here is a link that's a few weeks dated, but it'll serve for now:
http://www.bondresources.com/Corporate/Rates/AAA
The 30-year yield on AAA corporates is about 6.25%.
