Ordinarily, you'd expect good news from the housing market to lift the stock markets to new record highs. That's certainly been a pattern that investors have counted on lately, and today's report that new-home sales jumped 8.3% to their highest level since mid-2008 only continued a three-month streak of sales gains. Moreover, new-home prices have also posted sharp gains, rising 7.4% from June 2012 as inventories fell below the four-month mark, reflecting tight supplies.

During earnings season, though, investors often ignore those macroeconomic positives and focus instead on individual companies, and earnings results are largely responsible for this morning's drop in the Dow Jones Industrials (DJINDICES:^DJI), which has fallen 23 points as of 10:55 a.m. EDT.

Contributing the most to the Dow's decline is Caterpillar (NYSE:CAT), which is down 2.2%. The construction and mining equipment maker reported an even larger pullback in earnings and revenue than investors had expected, with earnings per share falling 43% on a nearly 16% decline in sales. Given the poor levels of global construction activity and the big declines in commodity prices during the second quarter, the news wasn't a huge surprise, but Caterpillar also cut its full-year 2013 earnings guidance by $0.50 per share to $6.50. Although the company will implement further cost-cutting measures throughout the rest of the year, Asia continues to weigh heavily on Caterpillar's sales, which dropped 21% in the region. Any recovery for Caterpillar will likely take longer than expected unless economies around the world rebound quickly.

Also falling is AT&T (NYSE:T), down 1.8%. Even though the telecom giant managed to boost its revenue by 1.6%, earnings fell slightly as the company spent money on major promotional discounts to encourage trade-ins of old smartphones. Moreover, smartphone subsidies continue to weigh on near-term earnings, even though the company gradually recoups those subsidies with its higher-priced data plan. If the company can't start controlling its costs more effectively in the future, then further profit declines could prove inevitable for AT&T.

Finally, on a more positive note, American Express (NYSE:AXP) is the biggest winner in the Dow, rising 1.4% after it issued a statement responding to the recent European Commission proposal to implement caps on credit card and debit card transactions. The company noted that the proposal wouldn't regulate the discount rate it charges merchants and that caps wouldn't directly cover proprietary transactions and commercial payments. Given the hit that AmEx stock took when the proposals were first announced, investors appear to be breathing a sigh of relief that they won't have an even bigger impact on AmEx's business going forward.

Fool contributor Dan Caplinger has no position in any stocks mentioned. You can follow him on Twitter @DanCaplinger. The Motley Fool recommends American Express. Try any of our Foolish newsletter services free for 30 days. We Fools may not all hold the same opinions, but we all believe that considering a diverse range of insights makes us better investors. The Motley Fool has a disclosure policy.