Although we don't believe in timing the market or panicking over daily movements, we do like to keep an eye on market changes -- just in case they're material to our investing thesis.

Given the huge gains the stock market has posted recently, sending major benchmarks to all-time record highs, today's pullback isn't all that extraordinary. Even though the Dow Jones Industrials (DJINDICES:^DJI) have fallen 88 points as of 12:50 p.m. EDT, the drop only takes the average back to where it set a new record less than three weeks ago.

When you dig deeper into the Dow to see which stocks are posting losses, though, you see some interesting patterns. News-related items like the downgrade of IBM are clearly driving some stock moves, but a few declines are more surprising.

For instance, given the lowest trade-deficit figures since 2009 and record exports, you wouldn't expect industrial giants Caterpillar (NYSE:CAT) and United Technologies (NYSE:UTX) to be losing out today. Today's trade deficit report highlighted rising export volumes of aircraft engines and heavy machinery as big contributors to the overall increase in exports, so you'd expect heavy-equipment maker Caterpillar to benefit, along with United Tech and its key Pratt & Whitney engine business. With United Tech, a roughly 15% rise in its share price since late June could have left investors more comfortable taking profits, but Caterpillar stock has performed badly all year. It's apparent that shareholders aren't at all confident that global economic activity is strong enough to rule out the possibility that the export figures were merely a short-term aberration.

Wal-Mart (NYSE:WMT) is another somewhat surprising decliner, falling almost 1%. Wal-Mart often outperforms the Dow during declines, as investors like the retailer's attractiveness to shoppers facing tough economic times. But Wal-Mart's drop reflects a couple of things. First, the company's Mexican subsidiary reported a 3.1% drop in same-store sales, pointing to weakness in emerging markets that could threaten the company's international growth. Moreover, the Dow is slipping in part because the economy is so strong that investors are anticipating the termination of the Federal Reserve's stimulus efforts, so Wal-Mart could actually see customers rise out of its target audience to boost prospects at mid-range and luxury retail competitors.

Finally, JPMorgan Chase (NYSE:JPM) has fallen about 0.8%. Favorable home-price data would ordinarily bolster the outlook for the bank's mortgage business, and although rising rates are a headwind to mortgage activity, they also raise the prospects for net interest margin and income. Yet even as the stock has soared, JPMorgan still has to address fundamental changes in the industry that could make it inherently less profitable than it was before the financial crisis, and until those long-term issues resolve themselves, they might put a ceiling on how far the stock can soar.