Market Fluctuations of the Investor's Portfolio

1. Every investor who owns common stocks must expect to see them fluctuate in value over the years.
2. The behaviour of the DJIA since our last edition of Intelligent Investor was written in 1964 probably reflects pretty well what has happened to the stock portfolio of a conservative investor who limited his stock holdings to those of large, prominent, and conservatively financed corporations.
3. The overall value advanced from an average level of about 890 to a high of 995 in 1966 (and 985 again in 1968), fell to 631 in 1970, and made an almost full recovery to 940 in early 1971.
4. (Since the individual issues set their high and low marks at different times, the fluctuations in the Dow Jones group as a whole are less severe than those in the separate components.)
5. We have traced through the price fluctuations of other types of diversified and conservative common-stock portfolios and we find that the overall results are not likely to be markedly different from the above.
6. In general, the shares of second-line companies fluctuate more widely than the major ones, but this does not necessarily mean that a group of well-established but smaller companies will make a poorer showing over a fairly long period.
7. (Today's equivalent of what Graham calls "second-line companies" would be any of the thousands of stocks not included in the Standard & Poor's 500-stock index. A regularly revisited list of the 500 stocks in the S & P index is available at http://www.standardandpoors.com/. )
8. In any case, the investor may as well resign himself in advance to the probability rather than the mere possibility that most of his holdings will advance, say, 50% or more from their low point and decline the equivalent one-third or more from their high point at various periods in the next five years.
9. (Note carefully what Graham is saying here. It is not just possible, but probable, that most of the stocks you own will gain at least 50% from their lowest price and lose at least 33% from their highest price - regardless of which stocks you own or whether the market as a whole goes up or down. If you can't live with that - or you think your portfolio is somehow magically exempt from it - then you are not yet entitled to call yourself an investor.)
10. (Graham refers to a 33% decline as the "equivalent one-third" because a 50% gain takes a $10 stock to $15. From $15, a 33% loss [or $5 drop] takes it right back to $10, where it started.)
11. A serious investor is not likely to believe that the day-to-day or even month-to-month fluctuations of the stock market make him richer or poorer.
12. But what about the longer-term and wider changes? Here practical questions present themselves, and the psychological problems are likely to grow complicated.
13. A substantial rise in the marke is at once a legitimate reason for satisfaction and a cause for prudent concern, but it may also bring a strong temptation toward imprudent action.
14. Your shares have advanced, good! You are richer than you were, good! (1) But has the price risen too high, and should you think of selling? (2) Or should you kick yourself for not having bought more shares when the level was lower? (3) Or - worst thought of all - should you now give way to the bull-market atmosphere, become infected with the enthusiasm, the overconfidence and the greed of the great public (of which, after all, you are a part), and make larger and dangerous commitments?
15. Presented thus in print, the answer to the last question is a self-evident no, but even the intelligent investor is likely to need considerable will power to keep from following the crowd.
16. It is for these reasons of human nature, even more than by calculation of financial gain or loss, that we favour some kind of mechanical method for varying the proportion of bonds to stocks in the investor's portfolio.
17. The chief advantage, perhaps, is that such a formula will give him something to do.
18. As the market advances he will from time to time make sales out of his stockholdings, putting the proceeds into bonds; as it declines he will reverse the procedure. These activities will provide some outlet for his otherwise too-pent-up energies.
19. If he is the right kind of investor he will take added satisfaction from the thought that his operations are exactly opposite from those of the crowd.
20. (For today's investor, the ideal strategy for pursuing this "formula" is rebalancing.)

Ref: Intelligent Investor by Benjamin Graham