This was a quick, enjoyable read. It took me about 4 to 4.5 hours to read which made me feel quite productive. I'm usually a very slow reader but I suppose this went quicker since I'm fairly acquainted with the subject.
There are a few quotes that I enjoyed and would like to share (1) "The investor's chief enemy is likely to be himself" (2) "The rate of return should be dependent, rather, on the amount of intelligent effort the investor is willing and able to bear on the task" and
(3)"To have a true investment there must be present a true margin of safety. And a true margin of safety is one that can be demonstrated by figures, by persuasive reasoning, and by reference to a body of actual experience."
The main thrust of the book is a lost chapter regarding how to value a stock that is growing. The author produced the the lost chapter in this particular book. For enterprising readers this can also be found in the 4th edition of Security Analysis. It wasn't include in the 5th edition. Graham scholars will also likely voice their skepticism how much this chapter was written by Graham and how much was written by Sidney Cottle (Graham wrote the first three editions of Security Analysis by himself while Dodd helped with note-taking). That being said, there is a lot to like in the book. It was written for the general reader so the analysis doesn't go into too much depth but, like Graham, that is also the strength of the book, meaning, everything is include in this book for the enterprising investor to analyze a company. This does assume the reader has a good grasp of accounting and other subjects but it is quiet useful for simple companies.
I appreciated the fact the author points out the flaws of the sharpe ratio (sharpe assumes stationary variance) another is the difficulty of estimating interest rates. For example, from 65-82 interest rates went up dramatically, thus, if someone assumed stable interest rates through that time period (which was fairly close from the 50's to mid 60's) that would have resulted in overestimating the return (higher interest rate will reduce the rate of return) or from 82-2000 interest rates went down dramatically, this would have resulted in underestimating returns if a model included higher rates.
Graham liked to keep things simple. For example, if there is a 90% probability of 5 variables, the probability of getting that problem correct is about 59%. If a problem has 9 variables and they all have a 90% probability, the probability of that problem working out is about 38%. Buffett used an example similar to that at an annual meeting once and I never forgot it. It is easy in this media rich world to be "led astray"-as brother Malcom would say-from charlatans and salesman talking about high growth rates that simply fail to pass the smell test once simple arithmetic or probability is employed. If one wants to argue with growth rates that are too high, they should go into sales and not into security analysis, but I digress. Graham believed anything higher than elementary algebra to ascertain the value of a company is not only inefficient but dangerous, meaning, it invites a false precision. Indeed, this actually a large reason for the most recent bubble we had that popped in 2008, although, to be fair, bubbles will happen without models using higher mathematics and assuming a false precision. This can be observed from a cursory reading of financial history going back to tulip mania in the 1600's.
One formula that is used in the book is Intrinsic Value= 8.5 plus (2 times g) times earnings per share.. For example, assume that company A has earnings per share of 1 dollar, further assume that the growth rate is 10% and the time to model this is 7 years then in 7 years earnings per share is 2 dollars. We would multiply 2 times 10 or 20 then add 8.5 or 28.5 for the result. IV in this case would be 20x2 equals 40 plus 8.5 equals 48.5. Of course, the lower the growth rate, the lower the p/e multiple. This would obviously not be used in isolation but it could be helpful after doing a more in depth analysis and using it as one additional step. Graham was brilliant and could have employed esoteric math (Columbia asked him to be a Professor in the Maths department when he was in his early 20's) but he simply thought this wasn't useful or accurate. After all, if someone was looking at buying a coffee shop or apartment down the street, if they used several spreadsheets and consulted with a Phd in maths, that wouldn't help in determining the value of the enterprise, it may even hurt.
This was an enjoyable read. I also like the chapter on competitive advantage. I thought this book might try and completely twist Graham and take him completely out of context and although there is a little bit of that due to the emphasis on the formula above, there is enough in the book to bring it almost back into balance and give the reader a reasonable exposure to Graham along with some chapters that was out of Graham's baliwick (such as the chapter on competitive advantage which was a joy to read as well).