What happened

Shares of The Priceline Group Inc. (NASDAQ:BKNG) have been gaining altitude this year, riding the bullish wave in the online travel bookings sector. The stock is up 36% as of July 19 according to data from S&P Global Market Intelligence.

A plane taking off against a colorful sunrise

Image source: Getty Images.

The stock has steadily gained as an expanding global economy has favored travel stocks:

PCLN Chart

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So what 

Priceline has risen tandem with rival Expedia (NASDAQ:EXPE) as both companies have put up strong numbers this year. Shares of recent IPO Trivago (NASDAQ:TRVG) have more than doubled this year, a sign of a healthy appetite for online travel-agency stocks.

Priceline's best day of the year came after it reported fourth-quarter earnings on Feb. 27, sending the stock up 5.6% the following day. Revenue in the period was up 17.4% to $2.35 billion, beating estimates at $2.32 billion, while adjusted earnings per share jumped $14.21, easily beating the analyst target at $13.01. Growth in hotel room nights, the company's biggest segment, accelerated to 31%, its fastest growth rate in more than two years. 

Priceline shares gained again in anticipation of its first-quarter earnings report, but the company offered disappointing guidance, sending the stock down 4.5%. Revenue increased 12.6% to $2.42 billion, below estimates at $2.45 billion, while adjusted EPS increased 7% to $9.88, beating expectations. 

The parent of Booking.com rebounded over the following weeks and has moved higher through July as the EU approved its acquisition of Momondo.

Now what

There's no denying the success of Priceline's acquisition strategy. The stock has been one of the best-performing since the recession, up nearly 3,000% over the past 10 years. It has built a particularly strong position in Europe thanks to Booking.com. The addition of Momondo, which also owns Cheap Flights, should help its flight bookings business in Europe as well.

The travel industry remains strong despite concerns about Airbnb or President Trump's travel ban. Analysts have historically underestimated Priceline's growth, and the combination of those two factors should help the stock continue to outperform.