Costume actors to wait before the show at “Chian Tourism Day” Inauguration Ceremony in Ninghai Zhejiang Province on May 19, 2011 in Ninghai, China. Various activities in local famous historic sites are being held to mark the day “China Tourism Day” on May 19. (Photo by Lintao Zhang/Getty Images)

A rainbow appears over the Louisiana gulf May 26, 2010 in the Gulf of Mexico near Brush Island, Louisiana. (Photo by Win McNamee/Getty Images)

British prime minister Winston Churchill (1874–1965) stops to pet a cat at Liverpool Street Station, 24th May 1952. (Photo by Keystone/Hulton Archive/Getty Images)

A subway worker walks away after a train departed the station in central Pyongyang, North Korea May 7, 2016. (Photo by Damir Sagolj/Reuters)

A model poses with “The Wellbeing Toilet” the winning entry from a Dyno-Rod Initiative to create a new design for the domestic toilet at Central Saint Martins on November 18, 2013 in London, England. The concept was commissioned to mark 50 years of Dyno-Rod and World Toilet Day on November 19th, 2013 The “Wellbeing Toilet” looks at the health and wellbeing aspect of getting rid of your bodily waste by being sculpted to enhance the position of your body by enabling you to squat rather than sit. (Photo by Miles Willis/Getty Images for Dyno-Rod)

A woman shields her face from the sun as she rides her scooter in Ahmedabad, India May 20, 2016. (Photo by Amit Dave/Reuters)

An internally displaced Afghan girl holds a child at a refugee camp in Kabul, Afghanistan May 31, 2016. (Photo by Mohammad Ismail/Reuters)

Young girls attend a training session in MGFSO Olympic reserve school in Moscow on May 30, 2016. (Photo by Kirill Kudryavtsev/AFP Photo)