Earnings divergence: Big was good, small was not

Traders on the floor of the New York Stock Exchange.
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Big companies won big and small companies lost during the recently ended earnings season.

That helps explain why the S&P 500 stock market index, where large firms reside, has had a pretty strong quarter, while the Russell 2000, the domain of small- and mid-cap companies, has lagged.

It also sets up what could be a challenging time ahead if smaller companies don't help confirm the broader market's rally.

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For the quarter, about 70 percent of S&P 500 companies beat their substantially lowered expectations, registering 4.5 percent profit growth against estimates of just 3.4 percent.

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When all corporate reports—2,268—are counted, however, the earnings beat shrinks to a rather unremarkable 58.6 percent, according to Bespoke Investment Group.

That's the second-worst quarter since the market hit its March 2009 lows. In addition, barely more than half (53.2 percent) topped their revenue estimates. Top-line growth for the S&P 500 will likely barely beat 2 percent for the year.

Guidance continues to be downbeat as well, with negative outweighing positive by 4.5 percentage points.

Still, the market keeps moving higher. The is up 6.9 percent in the fourth quarter, while the , despite its recent meandering, has gained 3.7 percent.

"Some may be quick to dismiss the positive surprises because they have been driven by analysts lowering the bar going into earnings season," Savita Subramanian, equity and quant strategist at S&P Capital IQ, said in a note. "While this is true, it is no different than what we have consistently seen over the past two years."

What has been different is that companies have typically struggled on reporting days, despite the general earnings beats.

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Bespoke said the average return for companies on they day they reported was slightly in negative territory. Companies that missed on earnings were punished significantly more than those that beat were rewarded.

"The overall market made it through this season relatively unscathed, but this will be something to watch early on next earnings season," wrote Paul Hickey at Bespoke. "If investors continue to sell stocks on earnings, it will signify a shift in sentiment on corporate fundamentals."

This matters because expectations are high going forward.

Fourth-quarter earnings, which won't start coming in for another two months, are expected to rise more than 8 percent. That may sound robust but is down 1.5 percentage points from Oct. 1 expectations.

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That leads up to 2014 earnings, which are projected to grow 10.75 percent, according to S&P Capital IQ.

Next year is supposed to be one when corporate America breaks out from beating earnings expectations by cutting costs and not hiring. But if current trends hold, that thesis is about to be put to a substantial test.

—By CNBC's Jeff Cox. Follow him on Twitter @JeffCoxCNBCcom.