The CEO of Uber, Travis Kalanick, told The Financial Times that Uber is profitable except for its investments in China and other new markets. Uber is in a fierce battle for market share as the number two ride sharing service in China behind Chinese company Didi Chuxing. China is now Uber’s biggest market in the world when measured by number of rides and amazingly accounts for a third of its business worldwide.

“We have hundreds of cities that are profitable globally,” Kalanick said. “That allows us to invest in new places, and to sustainably invest in a very expensive place like China.” Uber had first-mover advantage in China but was quickly followed by Chinese company Didi Chuxing which was flush with investment capital and has now moved into over 400 cities, while Uber has only launched in 60 plus cities, but that is changing fast. Uber lost over $1 billion last year in China and may lose even more this year in order to launch in new cities and gain market share.

China has 16 cities with metropolitan populations of over 10 million making market launches challenging and expensive. By comparison, the largest city in the United States, New York City, has a population of (only) 8.2 million. “We are number two in China, which means that we still have a ways to go,” Kalanick said. “But we are putting everything on the field.” According to FT, Uber’s CEO spent nearly one in five days in China. “Travis was personally invested in the success of Uber in China to a much greater degree than any other country,” noted Allen Penn, head of Asia operations at Uber.

China was always thought of as a huge challenge for Uber, but with potentially huge rewards. “We like to go after the thing that seems impossible,” Kalanick told San Francisco based FT writer Leslie Hook. “It was pretty far-flung for us to try at that time – but that was also what made it exciting.”

In order to combat difficult Chinese regulations targeting foreign owned businesses the company launched in China different than other Silicon Valley heavyweights like Google and Facebook, they created a separate company called Uber China and brought in Chinese investors. This has allowed Uber to do business in China without being hampered by unfair Chinese regulations that favor Chinese based businesses.

That’s the good news. The bad news is that Uber competitor Didi Chuxing is dominating the market and out-competing Uber and has launched in many more markets. Last year it arranged 1.4 billion rides in China, more than Uber has done worldwide in its history.