Burton Malkiel's "A Random Walk Down Wall Street" is the book that popularized passive investing. As a Princeton professor and board member of the Vanguard Group, Malkiel brought the practical implications of the efficient market hypothesis to the general investing public. The ideas in this book are now so ubiquitously accepted, that I actually learned very little new information. However, I am pleased to have experienced the original source of this powerfully simple yet effective investment philosophy. To be clear, many academics, most notably Eugene Fama, contributed to the intellectual framework by providing the theory, data, and studies. John Bogle allowed the masses to take advantage of this theory by creating the Vanguard Group. Malkiel popularized the idea with this book.
The efficient market hypothesis states that the stock market accurately reflects all available information in current prices such that no individual investor can consistently earn extraordinary returns. If there were such a gauranteed method, other smart investors chasing similar profits would soon make the endeavor unprofitable. In fact, Malkiel and others say that price movements are random or without discernible pattern. The randomness comes in the form of new information, which, by definition, is random. A product's success or failure, an airliner crashing, the result of a court case, and countless other factors that impact companies constitute the news. However, this news is never perfectly foreseeable, and predictions are already factored into the price of the stock. For example, when ConocoPhillips wrote off over $30 billion in goodwill during the 4th quarter of 2008, the stock price did not tumble greatly. The news had already been incorporated.
This idea is proven most easily by the fact that 80% of fund managers fail to beat the market (usually an index fund they use as a target). This is because actively managed funds charge high fees and generate many more trades which must be taxed. Additionally, the 20% who do beat the market in any given year fail to reliably do so the following years. Therefore, it makes sense to mimic the market as cheaply as possible to ensure the highest possible return. Again, this does not mean that people can consistently earn abnormal rates of return. Even recognizing a bubble during the bubble (a difficult task in itself) does not ensure success. Shorting a stock too early or a tulip in Holland could prove disasterous if the bubble continues to expand. Also, recognizing consistent patterns such as the January effect does not mean they can be profitably exploited. Transaction costs often prevent exploiting differences from being worthwhile.
An interesting aspect not addressed by Malkiel in this edition is the ever decreasing cost of buying and selling securities. Zecco.com now allows free trade if you meet certain requirements. My theory is that as transaction costs diminish, so will the perceived "inefficiencies".
Interesting tidbits:
The Indian who sold Manhattan Island for $24 in 1626 would have more than $50 billion if he invested it at 6% interest compounded semiannually.
Neither technical analysis (following past stock prices through charts) nor fundamental analysis (predicting future earnings based on assumptions and guesses) have proven to consistently beat the market. Malkiel still prefers fundamental analysis to the chartists who ignore ALL information about the stock other than the past prices.
Diversification ceases to add additional benefits after 20 stocks or so; a portfolio of 20 stocks is as no more or less risky than a portfolio of 1000 stocks. These benefits come in the form of lower risk or volatility and more consistent returns. Index funds are generally well diversified, which is yet another reason to buy them. Diversification is the meat behind Modern Portfolio Theory, invented in the 1950s by Harry Markowitz of the University of Chicago who won the Nobel Price in Economics for his work. Diversification can be achieved through asset classes (real estate vs stocks vs bonds), company size (small, mid, and large cap), geography (U.S. vs Europe vs Asia), and other ways.
Bond investors got hammered from 1969 through 1981 because of an 8% rate of inflation, which was higher than their returns on the bonds. Additionally, despite real negative rates of return (loss of purchasing power) the bond holders had to pay regular income tax rates on their coupons. They were literally paying money on top of subsidizing the borrowers--a double whammy. Government inflationary and tax policy harmed a lot of people financially.
Dollar-cost averaging has benefits when done in a 401k plan with money yet to be earned. But, because stock prices tend to rise over time, it is better to put large lump sums such as inheritances or lottery winnings into the market relatively quickly.
Memorable quotes:
"[Compound interest is:] the greatest mathematical discovery of all time." - Albert Einstein
"Annual income twenty pounds, annual expenditure nineteen nineteen six, result happiness. Annual income twenty pounds, annual expenditure twenty pounds ought and six, result misery." - Charles Dickens, "David Copperfield"
"Patience is a necessary ingredient of genius." - Disraeli
"No scientific evidence has yet been assembled to indicate that the investment performance of professionally managed portfolios as a group has been any better than that of randomly selected portfolios." - Burton Malkiel