Why settle for ordinary quarterly reports?

I believe that the biggest factor in a stock's ability to beat the market is to beat the market's expectations. That's why I look every week at three companies that have humbled Wall Street's pros over the past few trading days. If a company has more in the tank than the analysts figured, capital appreciation often follows.

We can start with Lifeway (NASDAQ:LWAY). The country's leading distributor of kefir -- a probiotic dairy beverage that's popular with Eastern Europeans -- saw earnings triple to $0.15 a share in its latest quarter. Lifeway's results obliterated Wall Street's bottom-line expectations of $0.07 a share.

Wal-Mart (NYSE:WMT) clocked in with a quarterly profit of $0.88 a share. Analysts were perched at the $0.86 mark, and that's not including a $0.04-per-share hit that Wal-Mart suffered as a result of the strengthening dollar.

Wal-Mart rival Target (NYSE:TGT) reports this week, so keep Wal-Mart's performance in mind. The market may have overestimated retailer weakness. Even mainstream mall chains that aren't discounters have held up well relative to expectations, with American Apparel (NYSE:APP), Urban Outfitters (NASDAQ:URBN), and Macy's (NYSE:M) all topping Mr. Market's profit targets lately.

Finally, we have Sara Lee (NYSE:SLE) with a slice of pound cake. The food giant posted a loss of $0.02 a share, but that includes a laundry list of charges that add up to $0.31 a share. Remove the one-time hits, and Sara Lee would have earned $0.29 a share, comfortably ahead of its $0.24-per-share profit target.

So keep watching the companies that surpass expectations. Over time, doing so will be a rewarding experience for investors as the market rewards the overachievers. That's the kind of surprise we look for in the Rule Breakers newsletter service. Want in? Check out a 30-day trial subscription.

Either way, come back next Monday to learn about more stocks that blew the market away.

Don't have regrets about missing out on great stocks at today's low prices. Read what Fool contributor Selena Maranjian is saying about top stocks for the next 20 years.