Americans are drinking more and better-quality tequila, and not only in margaritas on Cinco de Mayo.

Tequila sales have been growing at an average rate of 5.6 percent a year since 2002, according to February figures from the Distilled Spirits Council of the United States. In 2014 alone, 13.8 million nine-liter cases were sold.

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The U.S. represents tequila’s largest market, with about 52 percent of global sales. America’s renewed thirst for mixed cocktails has been a boon for spirits overall, but especially for tequila. Meanwhile, sales in Mexico have remained flat largely because the market there is mature, with little room for growth.

The Distilled Spirits Council said that one of the keys to tequila’s U.S. growth has been distillers’ ability to offer a product for every budget and occasion, but the fastest growth has been in high-end and super-premium brands.

“High-end brands have grown 189 percent in volume since 2002,” it noted. “Virtually unknown in 2002, super-premium tequila volumes have skyrocketed 568 percent and today account for 2.4 million 9-liter cases.”

Celebrity endorsements may have also raised the status of tequila. George Clooney, Sean Combs and Justin Timberlake have all promoted tequila brands.

In addition, distillers are trying to boost the popularity of high-end tequilas further by offering tastings and tours — at least one of which is aimed at the super-wealthy.

Tequila Avion, an ultra-premium tequila maker, is offering a $500,000, three-day trip for 10 to Jalisco, Mexico, to taste its spirits and partake of luxury accommodations, butler service and a private dinner among other amenities.

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If that seems a tad pricey, Experience Tequila in Portland, Ore., offers four-day tours to Mexico for just under $1,500, and you can find tequila-tasting classes in many cities for about $100.