Danielle Collins of the US reacts to a point in the first set while playing Caroline Wozniacki of Denmark during Round Two Women's Singles tennis match of the 2019 US Open at the USTA Billie Jean King National Tennis Center in New York on August 29, 2019. (Photo by Robert Deutsch/USA TODAY Sports)

A mural on an apartment block created as part of the Urban Morphogenesis street art festival in the Novaya Tryokhgorka residential neighbourhood in the town of Odintsovo in Moscow Region, Russia on August 31, 2019. (Photo by Valery Sharifulin/TASS)

Cosplayers dressed as She- Ra and Emma Frost pose for a photograph at the MCM Comic Con at ExCeL exhibition centre in London on October 28, 2017. (Photo by Tolga Akmen/AFP Photo)

Unsettled life in Europe failed to change the slow pace of life on the Isle of Capri, off Naples, Italy. Some of the socialites who have come there to relax enjoy an aquatic luncheon serviced in the cool Mediterranean, September 1, 1939. Swimming waiters push out the floating tables bearing meals which include wine and spaghetti. In the background are the rocks of Faraglioni. (Photo by Hamilton Wright/AP Photo)

Ryon Healy #25 of the Oakland Athletics is covered in water by Adam Rosales #16 after he hit a walk-off home run in the ninth inning against the Detroit Tigers at Oakland Alameda Coliseum on May 7, 2017 in Oakland, California. (Photo by Ezra Shaw/Getty Images)

Kosovo- born British singer and actress Rita Ora performs in Pristina on February 17, 2018 on the occasion of the 10 th anniversary of Kosovo Independence. Kosovo celebrates 10 years since it declared independence, a moment of pride for its ethnic Albanian majority, although sovereignty remains fiercely contested by Serbia. (Photo by Armend Nimani/AFP Photo)

A group of 1000 customers receive a facial massage at a sports centre in Jinan, Shandong province, China, May 4, 2015. A group of 1000 women were given a 30 minutes facial beauty treatment together on Monday that achieved a Guinness record for the largest group of people having beauty treatment in the same location, according to local media. (Photo by Reuters/Stringer)

More than 6 billion people live in countries where serious levels of public sector corruption are fueling inequality and exploitation, according to Transparency International's 2015 index of perceived public sector corruption. The group's annual report measures perceptions of corruption due to the secrecy surrounding most corrupt dealings. Two thirds of the 168 countries assessed were identified as having a serious corruption problem. Somalia, which has been mired in conflict since civil war broke out in 1991, ranks bottom of the list. (Photo by Feisal Omar/Reuters)