Читать книгу A Wealth of Common Sense - Carlson Ben - Страница 10

One of the biggest mistakes investors make is letting their emotions get in the way of making intelligent investment decisions. Research shows individuals sell winning stocks and hold on to losing stocks. They chase past performance and make decisions with the herd, buying more stocks after a huge run-up in price and selling after a market crash.16 These errors cost investors a lot of money when compounded over very long time horizons.

Even with all of the advantages outlined in the previous section, professional investors are not immune from making these same exact mistakes. Researchers looked at a dataset of more than 80,000 annual observations of institutional accounts from 1984 through 2007. These funds collectively managed trillions of dollars in assets. The study looked at the buy and sell decisions among stocks, bonds, and externally hired investment managers. The researchers found that the investments that were sold far outperformed the investments that were purchased. Instead of systematically buying low and selling high, these professional pools of money bought high and sold low. We often hear of individual investors buying and selling mutual funds at the wrong times (we'll get to that later), but this study shows that professional investors practice this same type of money-destroying behavior. In fact, the authors of the study figured that these poor decisions caused this group of investors to lose more than $170 billion.17

Another study looked at large pension plans. These funds had an average size of $10 billion each, but they also made the mistake of chasing past performance. Nearly 600 funds were studied from 1990 to 2011. The authors of the study found that these sophisticated funds allowed their stock allocation to drift higher when the markets were rising in the bull market of the late 1990s, making them overweight to their target asset allocation percentages. So when the market crashed they held more stocks than their policies and risk controls suggested. And following the financial crisis in 2008, these funds were far underweight in their target equity allocations and kept them low. These pension funds didn't factor in reversion to the mean. All they did was extrapolate the recent past into their current decisions. They didn't rebalance by buying low and selling high. To stay within their stated objectives they should have been trimming stocks in the late 1990s as they ran up higher and buying stocks after the crash in 2008, but that's not what happened at all. Instead they were fighting the last war and investing through the rearview mirror instead of sticking to their investment policy guidelines. Risk management was secondary to chasing returns.18