Every investor who owns common stocks must expect to see them fluctuate in value over the years.

Market Fluctuations of the Investor’s Portfolio

Every investor who owns common stocks must expect to see them fluctuate in value over the years. 

The behavior of the DJIA since our last edition 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.

• 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. 
• (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.) 
• 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. 
• 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. 

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.†




* 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 revised list of the 500 stocks in the S & P index is available at www.standardandpoors.com.

† 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. 
• (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.

Ref:  Intelligent Investor by Benjamin Graham