The Dow Jones Industrials (DJINDICES:^DJI) inched back into positive territory after opening the morning lower, up nearly two points as of 11 a.m. EST. Even though Home Depot (NYSE:HD) posted strong results in its fourth-quarter earnings report to lead all Dow gainers, downward pressure from Boeing (NYSE:BA) and Caterpillar (NYSE:CAT) helped keep the blue-chip index from a larger earnings-led lift.

Home Depot's results confirmed the relative strength of the home improvement retail industry, with earnings that beat expectations. Revenue dropped 3% from the year-ago quarter, but that was largely due to a quirk of the calendar that meant there was one less week during the quarter than there was for the same period in 2012. Investors were willing to shrug off 2014 guidance that didn't quite match up to hopes, with Home Depot expecting 4.8% higher sales and giving an earnings projection that was about 1% lower than analysts forecast. Nevertheless, the big question facing Home Depot going forward is whether winter weather will give way to a strong spring season, or if the economic malaise from the harsh winter will continue into the rest of 2014.

Meanwhile, Boeing fell almost 1%. The company got good news from the Pentagon yesterday, with Defense Secretary Chuck Hagel saying he would prefer to stick with a new air-refueling tanker program that Boeing is building. Today, however, there were reports that the company is having trouble selling unfinished early versions of its 787 Dreamliner aircraft, with customers preferring newer versions that are lighter and have a longer range. The issue shows the danger of long delays between taking orders and producing aircraft, as customers won't be happy receiving older models when new and better planes are available.

Similarly, Caterpillar fell almost 1.2%. The company has had an impressive run in 2014, as value investors bet on a turnaround in the construction industry that could lead to more sales of heavy equipment. Yet Home Depot's mixed guidance points to potential struggles in residential construction, and investors likely extended that outlook to commercial construction as well. With Caterpillar desperately needing a cyclical upturn, it's unclear whether shareholders will see the stock sustain its gains if conditions don't improve soon.

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