The 20 most important cities in global finance this year

There is fierce competition every year for a space on Z/Yen's Global Financial Cities Index, and 2015 is no different.

The ranks take a look at a each of the cities on the list and give them all city a combined score based on five main factors:

• Business environment
• Financial sector development,
• Infrastructure
• Human capital
• Reputational and general factors.

There was a huge reaction when New York dethroned London as the world's top financial hub last year - but has London managed to take the crown back? And how are Asia's growing megacities doing as China's rapid growth cools?