The new MacBook Pro is displayed in a case following the keynote address at the Apple 2012 World Wide Developers Conference (WWDC) at Moscone West on June 11, 2012 in San Francisco, Calif. Apple's most recent quarterly earnings report was disappointing. - 

Tess Vigeland: And we are in the heart of corporate earnings season. As we mentioned yesterday on the program, Apple's quarterly results disappointed. But today Caterpillar did better than expected.

There's something interesting going on in this earnings season, and it's not entirely about earnings. Marketplace's Mark Garrison explains what the corporate numbers so far tell us about the economy.

Mark Garrison: Two-thirds of companies reporting results so far have beaten analyst expectations for earnings. But you’re missing a big part of the story if you only look at that bottom line.

Thomson Reuters earnings analyst Greg Harrison says the interesting numbers right now are on the top line.

Greg Harrison: Revenues are currently on track to grow less than 1 percent for this quarter.

That’s positive, but barely, and sales growth is slowing. Harrison’s analysis shows more companies than usual are missing expectations on revenue. Six out of 10 fell short.

Miller Tabak equity strategist Peter Boockvar says revenue reveals...

Peter Boockvar: Revenue can’t be manipulated, where earnings can be, so the top line really reflects the environment that companies are selling into.

Sales for Apple came in $2 billion lower than expected, in part because of weak sales in Europe. Boockvar recommends kicking the tires of any company earnings reports.

Boockvar: You have to look under the hood to see what drove those earnings, especially if the revenues missed expectations. There are levers that companies can pull that could drive earnings without the same kind of revenue growth that they’re used to.

Levers like accounting moves. But there’s a more important factor at play for these companies, says Brian Wesbury, chief economist at First Trust Advisors.

Brian Wesbury: They are raising their productivity.

Productivity, of course, has a bright and dark side. Getting more done with less because of better technology is great. But another way to raise the profit per worker is to lower the amount of workers. So if companies don’t grow their revenues, there could be job cuts.

In New York, I'm Mark Garrison for Marketplace.

Follow Mark Garrison at @GarrisonMark