For months, investors have been talking about a potential all-time record high for the Dow Jones Industrials (DJINDICES:^DJI). Today, the market took a run at the mark, boosted by favorable economic data and, for the moment, ignoring concerns about sequestration and global macroeconomic issues. In the end, though, the Dow fell short, and ended up losing about 21 points, leaving it more than 100 points shy of its closing record.

Several stocks in the Dow helped hold the average back. Health-insurance giant UnitedHealth (NYSE:UNH) fell almost 1%, as the company continued to struggle in the wake of last week's news about a potential slashing of reimbursement rates under Medicare Advantage supplemental insurance plans. A Wall Street analyst said that, even with the recent drop in UnitedHealth and other insurance companies, the increasing need for the federal government to keep health-care costs in check could lead to greater pressure on profits than investors are counting on. As long as the nation's long-term budget woes remain unaddressed, these potential problems aren't going to go away.

Boeing (NYSE:BA) also dropped two-thirds of a percent, as it continues to struggle with the grounding of its 787 Dreamliner. Although relatively few planes have shipped to carriers in the U.S., Japanese airlines are much more exposed to the current fate of the airliner, and Boeing has had to work closely with Japanese regulators to assure them that the company's proposed fix to prevent lithium-ion battery overheating is more than just a temporary stop-gap measure. The faster Boeing can put safety concerns behind it, the sooner it can focus on getting planes built and delivered in a timely fashion.

Beyond the Dow, bad earnings news sent Groupon (NASDAQ:GRPN) plunging about 25%. The company surprised investors by failing to post a profit for the quarter, but the really bad news came from its first-quarter revenue projections, which could come in as low as flat compared to last year's quarter. After the bell, Groupon announced that it had replaced CEO Andrew Mason, sending shares higher immediately thereafter in after-hours trading. Although the company has assured investors of its plans for growth, Groupon needs the numbers to confirm its success if it wants to rebound from its steep losses.

Finally, J.C. Penney (NYSE:JCP) crashed 17% after it, too, disappointed investors with a negative earnings report. A huge net loss and plunging same-store sales resulted in a bond-rating downgrade, and raised questions about how long the company can sustain its high cash-burn rate. Although some analysts pointed to some positives from J.C. Penney's restructuring efforts, investors are getting impatient, and need to see tangible results sooner rather than later in order to regain confidence in the stock.