To paraquote the late, great Vince Lombardi, "What the <bleep> is goin' on out there!?"

I'll grant that Aetna's (NYSE:AET) first-quarter report wasn't exactly a work of brilliant outperformance, and I realize the loss of member data looks bad (as does the retirement of both the chairman and the CFO), but c'mon already. Even in a bad market for managed health companies, I'm not sure a 21% drop is what you'd call an example of an efficient market.

As far as the straight numbers go, things didn't look that bad. Revenue was up 15% (and beat the estimate), while operating earnings per share were up more than 30% if you exclude favorable reserve developments in the year-ago period. Now, I'll grant that margins weren't fantastic -- the company beat the revenue estimate by a fair margin but just squeaked by the EPS number.

And my hunch is that the cost trends are a big part of what has people spooked. Medical cost ratios worsened on both a sequential and year-over-year basis, and gross health-care expenses were up about 19% from last year. So I would imagine, then, that people are now a fair bit more skittish about whether cost trends for this company will stay within (or under) company guidance.

By no means do I want to minimize the potential negative impact if costs do get out of hand. How efficiently you run your business is the name of the game. True, service matters, but if you can't keep a lid on your costs and you have to raise your premiums faster than the market, the likes of WellPoint (NYSE:WLP) and Motley Fool Stock Advisor pick UnitedHealth (NYSE:UNH) may take that business away from you.

There were also two other items of news that weren't positive. First, the company announced that the chairman and CFO are both retiring. Second, the company announced the theft of a laptop that had information on 38,000 members. More likely than not, it's the first that has people more worried (unfortunately, people now seem to regard data theft like a thunderstorm -- unpleasant and scary, but inevitable) -- particularly if you think this is the beginning of the end of this great cycle in managed care, and so these folks are riding off into the sunset.

I'm frankly puzzled by the scope of today's drop, so I'm not recommending that you rush in to buy. Maybe the shares really are cheap now, but I'm also willing to concede I might be missing something here and things really are worse than I think. Tread carefully, fellow Fools, as the Street has taken a "shoot first and don't ask questions" approach to managed care these days.

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Fool contributor Stephen Simpson has no financial interest in any stocks mentioned (that means he's neither long nor short the shares).