wells fargo bank vaultreport by Global Finance Magazine.

The study compares 500 of the world's largest banks and their "long-term foreign currency ratings" issued by Fitch, S&P, and Moody's as of August 2014.

The banks are then given a score where 10 points are awarded for a AAA rating, 9 points for AA+ rating, and so on, according to Andrew Cunninghamproject coordinator for Global Finance Magazine.
The ranking does not include banks owned by other banks and government import-export finance institutions.