South Asian countries in terms of total contribution of travel and tourism to GDP. #6. Vietnam, Total GDP: USD 202.6 billion (2016). Contribution of Travel and Tourism to GDP: 9.1% . Here: A boat in the Thu Bon River, Hoi An, Vietnam. (Photo by Domingo Leiva/Getty Images)

An adult helps a young girl light a cigarette as a band plays in the background in the village of Vale de Salgueiro, northern Portugal, during the local Kings' Feast Friday, January 5, 2018. The village's Epiphany celebrations, called Kings' Feast, feature a tradition that each year causes an outcry among outsiders: parents encourage their children, some as young as 5, to smoke cigarettes. (Photo by Armando Franca/AP Photo)

These Northern Lights “rainbows” have turned the sky greener than the Earth below. Vitaly Istomin, 26, spent several nights in freezing conditions under the stars in northern Russia’s Khibiny Mountains to capture the aurora’s “rainbows”. (Photo by Vitaly Istomin/Caters News Agency)

A reveller wearing a costume dances as she holds a dring during the carnival street parade in Valletta, Malta, February 25, 2017. (Photo by Darrin Zammit Lupi/Reuters)

A protestor gestures toward the White House on the Ellipse near the South Lawn of the White House during the Women's March on Washington January 21, 2017 in Washington, DC. Large crowds are attending the anti-Trump rally a day after U.S. President Donald Trump was sworn in as the 45th U.S. president. (Photo by Drew Angerer/Getty Images)

Festival goers having fun at the Balaton Sound music festival in Zamardi next to the Lake of Balaton, 110 km (68 miles) west of Budapest, July 6, 2017. (Photo by Zsolt Furesz)

A girl plays in the Eshash el-Sudan slum in the Dokki neighbourhood of Giza, south of Cairo, Egypt September 2, 2015. Residents of the slum clashed with police in late August, when about 50 ramshackle huts were destroyed and at least 20 people were injured by teargas, local media reported, as authorities attempt to clear the area and rehouse residents. The slum dwellers, some of whom have called Eshash el-Sudan home for 50 years, say there are not enough apartments built nearby to house them. The residents of the slum eke out a living by disposing of rubbish or baking bread. Schooling is too expensive for most of their children, who play with salvaged rubbish amid shacks made out of discarded wood and leather. (Photo by Amr Abdallah Dalsh/Reuters)

Lali carries balloons to sell on a beach in Mumbai, India, Sunday, October 11, 2015. The United Nations General Assembly marks October 11 as the International Day of the Girl Child, to recognize girls’ rights and the unique challenges girls face around the world. (Photo by Rafiq Maqbool/AP Photo)