The Queen and JK Rowling are once again the only two British women to feature in the Forbes Most Powerful Women list, which has been led by Angela Merkel for the third year running.

The German chancellor is ranked ahead of Brazil's president Dilma Rousseff, Melinda Gates, who co-chairs the Bill and Melinda Gates Foundation, Michelle Obama, and Hillary Clinton.

The Queen dropped from 26 to 40 on the 2013 list, while the Harry Potter author JK Rowling slipped from 78 to 93.

The list was heavy on top politicians, featuring nine heads of state who run nations with a combined GDP of $11.8tn. Merkel – who has been placed at the top of the Forbes ranking seven times – headed the list again, ahead of Rousseff, who came to power in Brazil in 2011. Hillary Clinton, who has featured in every Most Powerful Women list since the inaugural ranking in 2004, is in fifth place. Despite resigning as secretary of state earlier this year, Clinton remains one of the biggest political hitters on the international stage. The only former first lady to become a US senator, she is now hotly tipped to become the 2016 Democratic presidential candidate.

Clinton was one place behind the woman already in the White House, First Lady Michelle Obama, who climbed three places to reach fourth.

Apart from Clinton, there are 14 on the 2013 list who appeared on the inaugural list a decade ago: the head of the IMF, Christine Lagarde (7), Sonia Gandhi (9), Indra Nooyi, the chief executive of PepsiCo (10), chatshow host Oprah Winfrey (13), UN administrator Helen Clark (21), ABC chief Anne Sweeney (24), Sony Pictures co-chair Amy Pascall (36), the Queen (40), Fidelity president Abigail Johnson (60), Ho Ching, chief executive of Singapore state investment firm Temasek (64), news anchor Diane Sawyer (73), JK Rowling (93) and Fox news anchor Great Van Susteren (97).

The list features 24 corporate chief executives in control of $893bn in revenues, 16 of them founders of their own companies, including two of the three new billionaires to the list, Tory Burch and Spanx's Sara Blakely. The 14 billionaires featured in the list are valued at more than $82bn, according to Forbes.

Among the world's most powerful women are Africa's first female head of state, Liberia's Ellen Johnson Sirleaf, the first woman chief executive of at IBM, Ginni Rometty, and the first president of an Ivy League and of the Rockefeller Foundation, Judith Rodin.

Providing both light entertainment and philanthropy, Angelina Jolie (37), Shakira (52), Gisele Bundchen (95) and Beyoncé (17) were all recognised for their charity work.

There was a strong showing for women in Asia. Park Geun-hye, the South Korean president, comes in at 11, while Burma's pro-democracy leader, Aung San Suu Kyi, was at 29. After showing her mettle in the Australian parliament - where she gave the leader of the opposition a dusting-down and accused him of sexism – Australian PM Julia Gillard featured just behind in 28th position, with Thai prime minister Yingluck Shinawatra at 31. Asian entrepreneurs Zhang Xin (50), Sun Yafang (77) and Solina Chau (80) all made the list, as did Kiran Mazumdar-Shaw, India's first biotech entrepreneur.

Facebook's Sheryl Sandberg (6), Rometty (12) and HP's Meg Whitman (15) all represent women working in technology, while in the world of fashion, Miuccia Prada, Zara founder Rosalia Mera and Diane von Furstenberg all made an appearance.

Moira Forbes, president and publisher of ForbesWoman, said: "This year's Power Women exert influence in very different ways, and to very different ends, and all with very different impacts on the global community.

"Whether leading multibillion-dollar companies, governing countries, shaping the cultural fabric of our lives or spearheading humanitarian initiatives, collectively these women are changing the planet in profoundly powerful and dynamic ways."

The top 10



1. Angela Merkel, German chancellor

2. Dilma Rousseff, president of Brazil

3. Melinda Gates, co-chair, Bill & Melinda Gates Foundation

4. Michelle Obama, US First Lady

5. Hillary Clinton, former US secretary of state

6. Sheryl Sandberg, COO, Facebook

7. Christine Lagarde, managing director, IMF

8. Janet Napolitano, US homeland security secretary

9. Sonia Gandhi, president, Indian National Congress party

10. Indra Nooyi, CEO, PepsiCo