Research from the credit agency's Web monitoring services CreditExpert shows that the first four months of 2012 have already outstripped the entire of 2010 when 9.5 million pieces of personal information were illegally traded in global online forums.

Approximately 90% of the data traded during January - April this year consisted of password and login combinations. This dramatic surge is thought to be in part due to consumers having a spiralling number of online accounts.

Consumer research commissioned by the firm among a sample of 2000 UK adults reveals that the average Briton now has 26 different online accounts with 25-34-year olds being the most prolific, with no fewer than 40.

The number of online accounts is set to grow further, with nearly one in five of Britons (17%) signing up to six or more new accounts every month.

Despite this, Britons use an average of just five different passwords to keep their details safe, says Experian, with a quarter (24%) using a single password for the majority of profiles, and one in 25 (four per cent) sticking with the same login details for all their accounts.