Top row: General Motors CEO Mary Barra (Sipa USA via AP); Amazon CEO Jeff Bezos (zz/Dennis Van Tine/STAR MAX/IPx); Oprah Winfrey, TV host, actress, and CEO (Brad Barket/Invision/AP). Center: Christine Lagarde, President of the European Central Bank (Arne Dedert/picture-alliance/dpa/AP Images). Bottom: Pop star Taylor Swift (AP Photo/Nati Harnik); Chinese President Xi Jinping and Russian President Vladimir Putin (Sergey Guneyev, Sputnik, Kremlin Pool Photo via AP); Warren Buffet, chairman and CEO of Berkshire Hathaway (Sipa USA via AP).