Benjamin Graham Formula for Growth Stocks

Those of you grappling with perhaps the most difficult investing challenge of all, valuation, might be interested to know of a simple formula Benjamin Graham articulated in "The Intelligent Investor" for the valuation of growth stocks. In his words: “Our study of the various methods has led us to suggest a foreshortened and quite simple formula for the evaluation of growth stocks, which is intended to produce figures fairly close to those resulting from the more refined mathematical calculations.”

The initial formula as described by Graham was as follows: Intrinsic Value = EPS * (8.5 + 2g). In this case, g represents the expected annual growth “over the next seven to ten years”. 8.5x was therefore Graham’s effective base P/E for a no-growth company. 

This formula however took no account of prevailing interest rates. He revised his formula in 1974 as follows: Intrinsic Value = EPS * (8.5 + 2g) * 4.4 / Y where Y was the current yield on 20 year AAA corporate bonds. Since the financial crisis of 2008/09, the number of US companies achieving AAA ratings from the main credit agencies has dropped to low single figures, meaning that some indices in this area have been discontinued. But there are options and possible proxies, including Moody's Seasoned AAA Bond Yield Index.  

Is the Graham Formula Useful?

You can compare the fair value given by a two-stage discounted cash flows model with the fair value of Graham's Formula. The conclusion is that the formula broadly equates to the two-stage DCF value (with that set of assumptions at least!).

Watch Out For

Benjamin Graham however did provide a caveat to the use of this equation. Of companies with a below-par debt position, Graham wrote: "My advice to analysts would be to limit your appraisals to enterprises of investment quality, excluding from that category such as do not meet specific criteria of financial strength". In the book “Small Stocks, Big Profits”, Dr. Gerald Perritt summarised four quantitative caveats:

1. The firm must not be excessively levered, i.e. it should not have debt to total asset ratios greater than 60% of total assets.
2. The firm must have positive earnings (i.e. no losses)
3. The share price must be below net working capital per share.
4. The inverse PE (i.e E/P) should be greater than twice the AAA bond yield.

Arguably, however, this is confusing Graham's screening criteria with the valuation formula. The first two seems quite reasonable in any case. Of those criteria, the last two are the most severe and may be open to debate as they restrict use of the formula in most cases. Using say the Graham Multiplier constraint of 22.5 for P/E * P/B might be more suited to today's environment.  

How can I apply this? 

On Stockopedia Premium, of course! You can use the Ben Graham Rule of Thumb calculator to value any company using this approach.

From the Source:

Graham discusses the original formula on page 295 of the Intelligent Investor, available on Amazon. You can also however find Graham’s fascinating 1974 piece, “The Decade 1965-1974: Its significance for Financial Analysts” online.

Further Reading on the Graham Formula: 

• Wikipedia: Graham Formula
• TMF: Ben Graham’s Equation
• OSV on the Benjamin Graham Formula