A woman walks past graffiti on a wall in the Williamsburg neighborhood of the borough of Brooklyn, in New York, September 16, 2014. The picture was taken through car window with raindrops. (Photo by Shannon Stapleton/Reuters)

Child models present creations at Dong Wenmei T100 Children's Collection during China Fashion Week in Beijing October 29, 2014. (Photo by Kim Kyung-Hoon/Reuters)

Singer Rihanna poses at amfAR's fifth annual Inspiration Gala in Los Angeles, California October 29, 2014. (Photo by Mario Anzuoni/Reuters)

A woman photographs a Norwegian spruce Christmas tree from Oslo after it was lit at Trafalgar Square in central London, December 4, 2014. (Photo by Toby Melville/Reuters)

A performer from Cirque du Soleil's show “Quidam” practices backstage before a show at the MEO Arena in Lisbon December 18, 2014. (Photo by Rafael Marchante/Reuters)

Ukrainian servicemen sit atop an armored personnel carrier (APC) at a military base in the town of Kramatorsk, eastern Ukraine, December 24, 2014. (Photo by Valentyn Ogirenko/Reuters)

A man gestures to a robot at a restaurant in Hefei, Anhui province, December 26, 2014. The restaurant, with a space of 1300 square metres and a total of 30 robots to cook meals, deliver dishes and welcome costumers, was reported to be the biggest robot restaurant in China. (Photo by Reuters/Stringer)

Darts fan Nigel Panton in fancy dress ahead Day Eight of the William Hill PDC World Darts Championships at Alexandra Palace on December 28, 2014 in London, England. (Photo by Jordan Mansfield/Getty Images)