Viva Mexico!

Could there be any better way to describe America Movil's (NYSE:AMX) first-quarter results? Investors in Latin America's largest telecom operator will be ready for another celebratory shot of Tequila this Cinco de Mayo after reading these results. The company recorded revenue of $6.1 billion, up 28% from last year, and a dramatically improved EBITDA margin that came in at just less than 43%. The jump in revenues combined with the juiced margins led to net profits of $1.4 billion, 53% higher than last year.

The Mexican firm, controlled by billionaire Carlos Slim, once again blew by analyst expectations, in a strong demonstration that there's still abundant growth to be found -- not to mention profits -- in Latin America's wireless market. America Movil's affiliates across the Americas plumped up by 5.9 million subscribers in the past three months to increase its total base to hefty 131.2 million, a full 30% above last year's total. Even in its flagship and more mature market of Mexico, the company added 1.8 million subscribers.

Fellow Fool contributor Will Frankenhoff has said again and again that America Movil is on his short list of favorite plays in wireless. The combination of growing markets, strict operational management, and smart acquisitions has helped America Movil's American depositary receipts soar 48% in the past year. And the metrics America Movil reported this quarter confirm that the company is capable of efficiently capturing untapped growth across its markets.

In many ways, America Movil is benefiting from the same market condition that U.S. operators such as Verizon (NYSE:VZ), Sprint Nextel (NYSE:S), and AT&T (NYSE:T) found in the late 1990s -- a largely untapped population that was clamoring to become upwardly mobile. While Latin American customers predominantly favor prepaid plans, America Movil's economies of scale help it squeeze operating profits out of every market in which it offers service.

With a relatively low penetration in many Latin American markets, a cornucopia of subscribers still waits for America Movil and competitors such as Telefonica (NYSE:TEF) to tap. This gives investors some time still to see whether this international story of ample growth is right for their portfolio.

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Fool contributor Dave Mock waffles between diet and exercise. Wait, did someone say waffles? He owns no shares of companies mentioned in this article. Dave is the author of The Qualcomm Equation. The Fool's disclosure policy is so tasty, you can't eat just one.