"So much for business fundamentals driving stock market returns! What an old fashioned, primitive concept! Today it's all about central banks: if they ain't printing, they ain't helping!" Such is my simplistic personification of Wall Street's message to investors, as equities slumped Tuesday. Upon hearing that the Bank of Japan wouldn't print any more than the more than $700 billion equivalent it already pledged to print, stock markets tumbled today, and the Dow Jones Industrial Average (^DJI -0.11%) sank 116 points, or 0.8%, to close at 15,122.

UnitedHealth Group (UNH 0.23%) added 0.4%, ending as the Dow's best performer for a second straight day. The prominent health insurer was given an increased $79 price target yesterday by one research firm, and the stock carried its momentum forward from there. It finished as one of just three blue chips to advance Tuesday. The stock also goes ex-dividend tomorrow, which means shareholders on record as of Wednesday's close will receive the company's next quarterly dividend.

Pharmaceutical giant Pfizer (PFE -0.19%) joined UnitedHealth as one of the elite few to advance, but did so only barely, adding 0.2%. While little news of note broke on Pfizer today, the stock had a few things going for it to encourage some slight bullishness. Health care ended as the top-performing sector in the markets today, so that certainly didn't hurt. Also, despite having traded higher four straight days, it doesn't trade for a lofty valuation, going for under 14 times earnings.

Microsoft (MSFT 0.37%) shares took a beating today, losing 1.8%, as Sony unveiled its new PlayStation 4 gaming console. Retailing at $399 in the U.S., the PlayStation is $100 cheaper than Microsoft's Xbox One. On top of that, cost-conscious gamers reveled in the fact that the PlayStation 4 will allow unlimited used game sales, a key difference between the two devices. In short, Xbox One's competition already looks stiff.

Lastly, shares of Merck (MRK 0.10%) slumped 1.9%, as dividend investors fled high-yielding equities in the stock market today. Merck has the fourth-highest annual dividend yield in the Dow, dishing out about 3.6% per year to its shareholders. With Treasury yields climbing as further stimulus from Japan failed to come and markets brace for a slowdown in domestic quantitative easing, yield-oriented investors look more and more to Treasuries over dividend stocks.