A weeping South Vietnamese mother and her three children are shown on the deck of this amphibious command ship being plucked out of Saigon by U.S. Marine helicopters in Vietnam, April 29, 1975. (Photo by AP Photo)

Filipino Muslims ride on top of a vehicle as they celebrate the end of the holy month of Ramadan in Cotabato city, in southern Philippines, July 16, 2015. Picture taken July 16, 2015. (Photo by Marconi Navales/Reuters)

Belgian riot police officers are covered by hay and eggs thrown by demonstrators as farmers and dairy farmers from all over Europe take part in a demonstration outside an European Union farm ministers emergency meeting at the EU Council headquarters in Brussels, Belgium, September 7, 2015. Thousands of farmers gathered in the European capital calling for more help with low prices and high costs. (Photo by Jacky Naegelen/Reuters)

Men ride a motorcycle in front of destroyed houses after Hurricane Matthew passes Jeremie, Haiti, October 7, 2016. (Photo by Carlos Garcia Rawlins/Reuters)

The giant metal structure sits 330ft above the ground on the roof of a 22 storey office block in Dutch capital Amsterdam on September 6, 2016. Tourists sit in a playground-style chair as they propel themselves them over the edge of the building with only thin-air between them and the ground below. Engineers spent several years designing and building the breathtaking swing. By being fixed to the top of a building it reaches new heights – dwarfing other swings around Europe but trailing behind the 1,150ft high mechanical rides at the Stratosphere Hotel in Las Vegas, Nevada. (Photo by Huub Zeeman/SWNS.com)

America in the 1970s: Texas. Motorcyclist loading his possessions onto a truck with the help of his friends in Leakey, May 1973. (Photo by Marc St. Gil/NARA via The Atlantic)

Cocoa Beach, Florida, USA. 7th October, 2016. Kaleigh Black, 14, left, and Amber Olsen, 12, run for cover as a squall with rain and wind pelt them while they explore the Cocoa Beach Pier on Friday (10/7/16) after hurricane Matthew passed to the east on Florida's east coast.(Photo by Douglas R. Clifford/Tampa Bay Times/ZUMA Wire/Alamy Live News)

A girl gets her hands decorated with traditional henna patterns at a roadside stall ahead of Eid-al Fitr to mark the end of the holy fasting month of Ramadan in Karachi, Pakistan, July 17, 2015. (Photo by Akhtar Soomro/Reuters)