The Central Bank of Mexico reported that the number of fake bank notes removed from circulation in 2011 was around 9 percent higher than the number of counterfeit money detected in 2010. The biggest rate of increase in counterfeit currency in Mexico in 2011 was in the 50 peso note.
In the United Kingdom, the Bank of England reported that the number of counterfeit currency removed from circulation in 2011 was 24 percent higher than in 2010. The most counterfeited currency was the £20 note.
Source: Joe Sharkey, “Keeping an Eye Out for Counterfeit Money,” New York Times, November 26. 2012.