can see the guy with two shopping carts, the cashier
in training at register three,
the coupon queen lined up at register six. Everybody at the checkout tries to pick
the fastest line. Sometimes you will be right; sometimes you will be wrong. Over
time they will average out, so that if you go to the grocery store often enough,
you’ll probably spend about the same amount of time waiting in line as everyone
else.
Indeed, we can take the analogy one step further. Suppose that somewhere
near the produce aisle you saw an old woman stuffing wads of coupons in her
pockets. When you arrive at the
checkout and see her in line, you wisely steer
your cart somewhere else. As she gets out her coin purse and begins slowly
handing coupons to the cashier, you smugly congratulate yourself. Moments
later, however, you realize the guy ahead of you forgot to weigh his avocados.
“Price check on avocados at register three!” your cashier barks repeatedly as you
watch the coupon lady push her groceries out of the store. Who could have
predicted that? No one, just as no one would have
predicted that MicroStrategy,
a high-flying software company, would restate its income on March 19, 2000,
essentially wiping millions of dollars of earnings off its books. The stock fell
$140 in one day, a 62 percent plunge. Did the investors and portfolio managers
who bought MicroStrategy shares think this was going to happen? Of course not.
It’s the things you can’t predict that matter. Indeed, the next time you are
tempted to invest a large sum of money in a single stock,
even that of a large and
well-established firm, repeat these magic words: Enron, Enron, Enron. Or
Lehman, Lehman, Lehman.
Proponents of the efficient markets theory have advice for investors: Just pick
a line and stand in it. If assets are priced efficiently, then a monkey throwing
darts at the stock pages should choose a porfolio that will perform as well, on
average, as the portfolios picked by the Wall Street stars. (Burton Malkiel has
pointed out that since diversification is important,
the monkey should actually
throw a wet towel at the stock pages.) Indeed, investors now have access to their
own monkey with a towel: index funds. Index funds are mutual funds that do not
purport to pick winners. Instead, they buy and hold a predetermined basket of
stocks, such as the S&P 500, the index that comprises America’s largest five
hundred companies. Since the S&P 500 is a broad market average, we would
expect half of America’s actively managed
mutual funds to perform better, and
half to perform worse. But that is before expenses. Fund managers charge fees
for all the tire-kicking they do; they also incur costs as they trade aggressively.
Index funds, like towel-throwing monkeys, are far cheaper to manage.
But that’s all theory. What do the data show? It turns out that the monkey with
a towel can be an investor’s best friend. According to Morningstar, a firm that
tracks
mutual funds, slightly fewer than half of the U.S. actively managed
diversified funds beat the S&P 500 over the past year. A more impressive 66
percent of actively-managed funds beat the S&P 500 over the past five years.
But look what happens as the time frame gets longer: Only 45 percent of actively
managed funds beat the S&P over a twenty-year stretch, which is the most
relevant time frame for people saving for retirement or college.
In other words,
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