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 Air Methods (NASDAQ:AIRM), a provider of air medical transport services within the U.S., sunk nearly 13% Friday after the company reported its first-quarter earnings results after the closing bell last night.

So what: For the quarter, Air Methods produced a robust 24% increase in revenue to $223.1 million as community-based patient transports rose 9% to 12,941. Same-base transports (those in operation more than a year) rose 7%, while net revenue per transport surged 20% to $10,928. Also in the positive column, maintenance expenses, excluding its tourist operations, declined 16%. Profit for the quarter improved to $0.28 per share, reversing a year-ago loss of $0.15 per share. However, Wall Street blew off the nice rebound because its consensus estimate of $0.33 in EPS was missed.

Now what: The big problems for Air Methods in prior quarters have been higher than expected maintenance costs, seasonal variability, and uncooperative weather. While some of these factors are beyond the company's control, it appears to be doing a great job with what it can manage. Patient transports are up, and more importantly price per patient rose significantly. It ultimately comes down to this: Air Methods works in a space with little competition and a high barrier to entry. That alone makes the company an attractive candidate over the long run, as it boasts strong pricing power and something of a basic-needs status. With the stock at just 14 times forward earnings, today's dip is a potentially intriguing buying opportunity for long term-oriented shareholders.

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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