The Dow Jones Industrial Average (^DJI 0.67%) has wobbled in and out of the green throughout a trading day in which three of its blue-chip members have released quarterly data. As of 2:30 p.m. EDT, the Dow was down about 16 points. While industrial giant Caterpillar's (CAT 0.83%) stock has gained 1.7% following an earnings beat. fellow Dow members 3M (MMM 0.38%) and Verizon (VZ -4.67%) lost ground after delivering less than spectacular quarterly data. Let's catch up on what you need to know.

Caterpillar cruises ahead

Caterpillar's 789D Mining Truck. Source: Caterpillar Mining Image Gallery.

Caterpillar has had a rough go of late amid the industrial sector's downturn, particularly as sales of its heavy machinery plunged as the mining industry collapsed in the wake of the recession. That latter trend hasn't changed so far, as Caterpillar reported that its resource Industries division, responsible for the company's mining products, sustained a 37% year-over-year revenue drop for the quarter. Still, that didn't stop Caterpillar from posting impressive earnings growth that crushed average analyst projections, and the company's revenue just eked out a beat as well. The industrial company hiked its full-year bottom-line guidance on the rosy news. While Caterpillar still sees the mining industry in a slump, growing construction in North America and the company's cost-cutting measures should help it overcome that major challenge in the quarters to come.

Meanwhile, as 3M's stock has fallen 1% so far today. While the conglomerate managed to grow both revenue and net profit from last year's first quarter, both lines missed analyst expectations. The company expects currency issues to hit hard this year due to 3M's foreign presence, but it could make a big splash in 2014. 3M aims to spend between $5 billion and $10 billion on new acquisitions from now until 2017, and the company said in March that it expects China revenue to outpace total sales growth by a factor of three. If 3M can establish a dominant foothold in the world's second-largest economy, it will be in great position for the long term in capitalizing on China's middle class and urban growth.

Verizon stock has been the biggest loser on the Dow so far today, tumbling by 2.8%. The wireless giant posted fantastic quarterly profit growth behind its acquisition of Vodafone's stake in Verizon Wireless, but the adjusted earnings just missed analyst expectations despite a revenue beat. However, investors shouldn't worry too much about the earnings miss: Verizon's loss of phone customers for the quarter is the real shocker.

The company lost about 138,000 postpaid phone subscribers for the quarter as rivals chipped away at Verizon's leadership, a particularly stunning result considering that chief competitor AT&T (T -1.21%) posted fantastic postpaid customer growth for its own quarter. While Verizon managed to add more than 600,000 tablet customers for the quarter to outweigh that loss, it's still a result that needs to be watched closely in coming quarters. AT&T and other American telecom leaders have engaged in an all-out brawl for customers in a tightly contested market; if this quarter is any indication, the strategy has succeeded in cutting into Verizon's dominance. While AT&T still trails Verizon overall in the wireless market, it's shown that it won't succumb to second place without a fight.