Tourism is the single biggest revenue earner, growing from humble beginnings in 1980 to more than $7.4 billion by 2019. Successive governments have invested heavily in tourism development, creating upgraded airports and other infrastructure. The number of tourist amounted to 6.4 million tourists arriving in the country in 2019. Most come from Europe, with about 25 percent originating from the United States or Canada. The country now has almost 70,000 hotel rooms, more than any other Caribbean country. About 50,000 Dominicans are directly employed in this sector, mostly working in hotels, and another 110,000 are indirectly employed as taxi drivers, tour guides, or tourist-shop staff. Most tourists visit the Dominican Republic on account of its beaches, but there is an expanding eco-tourism and outdoor activity sector, focused on the country's mountains and wildlife.