In today's world, most companies span several regions and sell across the world. As Foolish colleague Morgan Housel notes, 10 years ago, less than a third of S&P 500 revenue came from overseas. Today, more than half of the S&P 500's growth comes from overseas.

And that number is growing. The truth is, investors regularly underestimate how much demand comes from abroad. More importantly, for large, multinational corporations that have already established a presence in their home markets, much of their future growth comes from abroad.

With that in mind, today we're looking at travel website Travelzoo (Nasdaq: TZOO). We'll examine not only where its sales and earnings come from, but how its sales abroad have changed over time.

Where Travelzoo's sales were four years ago
Four years ago, Travelzoo was just getting started in Europe, and its European operations accounted for only around 5% of company sales.

Editorial

Source: Capital IQ, a division of Standard & Poor's.

Where Travelzoo's sales are today
Today, Travelzoo still collects a majority of its sales from the United States, but the gap between U.S. and European sales is closing.

Editorial

Source: Capital IQ, a division of Standard & Poor's.

Travelzoo has long trumpeted Europe as a key growth market. In 2008, the company passed the 2 million-member mark on the continent. In the first quarter, the company saw its highest quarterly subscriber growth in Europe and posted its first "significant" quarterly profit on the continent. Today, Europe stands at nearly 5.1 million subscribers.

Like OpenTable (Nasdaq: OPEN) and The Knot (NYSE: XOXO), Travelzoo has been able to leverage its huge user base into the launch of a successful Groupon-esque Local Deals offering. That's helping drive additional sales volume in Europe. In the first quarter, Europe's Local Deals generated $3.4 million in revenue; through the first 45 days of the second quarter, Travelzoo has generated $3 million in Local Deals sales in Europe. That's an impressive total considering that its European operations recorded sales of just $9.4 million in the first quarter.

Competitor checkup
One last point to check is how Travelzoo's footprint compares to some of its peers across the broader travel site:

Company

Geography With Most Sales

Percent of Sales

Travelzoo United States 77%
priceline.com (Nasdaq: PCLN) United States 53%
Expedia (Nasdaq: EXPE) United States 62%
Orbitz Worldwide (NYSE: OWW) United States 76%

Source: Capital IQ, a division of Standard & Poor's.

As you can see, Travelzoo is a bit behind its peers when it comes to expanding outside of the United States. However, while the main challenge ahead of travel portals like Expedia and priceline.com in Europe is getting a more fragmented hotel industry around its offerings, Travelzoo can appeal to a wide base of email subscribers with sponsored deals that only require a smaller number of hospitality industry sponsors. Essentially, once it has built out its subscriber base, Travelzoo should be well-positioned to profit from the market.

Keep searching
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Eric Bleeker owns shares of no companies listed above. Motley Fool newsletter services have recommended buying shares of priceline.com and OpenTable. Try any of our Foolish newsletter services free for 30 days. We Fools may not all hold the same opinions, but we all believe that considering a diverse range of insights makes us better investors. The Motley Fool has a disclosure policy.