CHICAGO (MarketWatch) — Cost cuts, easy comparisons and revenue growth helped push the earnings of most S&P 500 companies handily past Wall Street’s third-quarter expectations.

And the companies have also been battling still-high unemployment, cautious consumers and currency headwinds.

The earnings strength has been broad-based, across a wide variety of industries with the big standouts thus far being financial services, industrials and information technology. In all, with roughly half of the S&P 500 SPX, +0.82% reporting by Thursday, 79% had exceeded expectations, with just 15% coming up short, according to data compiled by Thomson Reuters.

Fear has taken over

If that percentage holds, it would match the highest-ever level of companies beating estimates in a quarter — or at least since Thomson Reuters began tracking the statistics 16 years ago. The 79% mark was last hit in the third quarter of 2009, when the economy came off the rock bottom of late 2008.

“We are certainly on pace for that now,” said John Butters, director of U.S. earnings research for Thomson Reuters. “And it’s a continuation of a trend we have seen in the past four to six quarters.”

Although he notes that earlier beats may have in part been helped by analysts sharply cutting their estimates at the height of the economic meltdown, “We have seen very little of that lately. There might have been too much cutting 18 months ago.”

Some of the best numbers have come from big investment banks, with Bank of America Corp. BAC, +1.34% , Goldman Sachs Group Inc. GS, +2.12% , Legg Mason Inc. LM, +16.66% and Wells Fargo & Co. WFC, +1.07% all blowing away analyst targets, while Citigroup Inc. C, +1.62% merely edged past them. A total of 77% of the financial firms that have reported have topped estimates.

Technology is another category that is roaring. While a few giants have yet to release results — Microsoft Corp. MSFT, +1.48% , for instance, won’t be out until late Thursday — others have already reported, and the news was largely upbeat.

Apple Inc. AAPL, +1.50% recently reported a jump in third-quarter earnings to $4.64 a share from $2.77 on a 67% rise in revenue, as iPhone sales nearly doubled. Google Inc. GOOG, +0.01% reported a 32% increase in third-quarter profit to $2.17 billion, or $6.72 a share.

Ninety percent of the tech companies to have reported have surpassed Wall Street hopes.

“Tech is setting record levels of earnings, with solid revenue growth backing that,” Butters noted.

Industrials upbeat

In the industrial sector, where 88% of reporting companies have topped estimates, there have been some truly robust results. Last week, Caterpillar Inc. CAT, +1.18% posted a 96% jump in profit on sales of engines and other types of heavy equipment. It earned $1.22 a share, well above the expected $1.09, and beat on the top line as well.

“Continuing economic growth in the developing world has been key to improving sales,” Doug Oberhelman, chief executive, told investors. “Sales in developed countries have improved substantially after deep declines in 2009.”

The company also noted that 2010 is looking to be “one of the most significant year-over-year increases in sales and revenues” in its history, as it boosted its 2010 profit forecast to a range of $3.80 to $4 a share from a previous range of $3.15 to $3.85 a share.

“There are some signs of consumer life and some signs of industrial life, as well,” said George Van Horn, senior analyst at IBIS World. “Consumers are spending but not across the board. The general attitude seems to be a bit better than it was a year ago.”

He noted that the airlines did pretty well and are confident in their pricing power, while even trodden-down car makers “are either increasing their outlooks or becoming more confident.”

Still, he added that “most of the current optimism is looking into the fourth quarter and not necessarily putting a rosy view on 2011,” which could forestall any “dramatic surge” in the markets.

“You have to wonder about the market’s trajectory,” he said. “Even with all these good numbers, there is a lot of uncertainty about how 2011 will unfold and there are definitely some cost pressures coming on.”

For Butters at Thomson Reuters, “the fourth quarter is the last one with easy comparisons,” and growth estimates for 2011 are more modest.

“Analysts are looking for low-double-digit earnings growth and mid-single-digit revenue growth,” he said. “The numbers are more consistent.”