Merkel is followed by US presidential hopeful Hillary Clinton, with Janet Yellen, chair of the U.S. federal reserve, ranked in third Melinda Gates is ranked fourth U.S. First Lady Michelle Obama is the 13th most powerful woman, according to the rankings, which consider influence, media presence, money and success at implementing change. The Queen is the highest-placed British woman on the list, with her ranking rising from 41 last year to 29 in 2016. The list includes Christine Lagarde, head of the International Monetary Fund, at number six, one place ahead of Facebook chief operating officer Sheryl Sandberg. U.S. talk show host Oprah Winfrey is now 21st on the list. Anna Wintour, well-known for her role as editor in chief for Vogue magazine, is 28th.