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

What: Shares of AmSurg (NASDAQ:AMSG.DL), an operator of ambulatory surgery centers throughout the United States, tumbled as much as 11% after reporting its first quarter earnings results and providing guidance for the second quarter and remainder of the year. Shares have since recovered and are down around 4% as of this writing.

So what: For the quarter, AmSurg reported a modest 2% increase in revenue to $263.1 million from the year-ago period as net earnings dipped slightly to $17.5 million, or $0.55 per share, from $17.8 million, or $0.56 per share. By comparison, Wall Street was expecting revenue of $272.8 million and EPS of $0.57, meaning AmSurg missed on both accounts. AmSurg blamed the 2% decline in same-center revenue on the severe winter weather that blanketed much of the country in January and February. Looking ahead, it forecast second quarter EPS of $0.61-$0.64, and full-year revenue and EPS of $1.12 billion-$1.13 billion and $2.41-$2.45. All three figures, once again, fell slightly short of Wall Street's estimates and were a reflection of the inclement weather effect during the first quarter.

Now what: Even without the effect of inclement weather, it sounds as if AmSurg was on pace to deliver flat year-over-year results. I suspected that AmSurg would actually become a beneficiary of Obamacare in that fewer uninsured patients would lead to more frequent doctor visits. In addition, insured patients also reduce the worry of nonpayment by ambulatory center operators like AmSurg. But my thinking hasn't exactly worked out as of yet and AmSurg's growth has stalled save for a few small acquisitions. While I do like the business model and could see it succeeding over the long run, I'd wait for improved top-line growth before getting too excited about this stock.

Sean Williams has no material interest in any companies mentioned in this article. You can follow him on CAPS under the screen name TMFUltraLong, track every pick he makes under the screen name TrackUltraLong, and check him out on Twitter, where he goes by the handle @TMFUltraLong.

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