The total damages awarded against Japanese companies for errors in their financial statements increased four-fold to a record 45.9bn yen last year, according to a new report.

Economics consultancy Nera, which published the analysis, said the 2009 damages dwarfed the level recorded for 2008 – 9.9bn yen – and represented more than the total amount of securities litigation for the whole previous decade.

Damages were particularly high last year because a few particularly big cases were settled, which involved unusually large payouts. Nera said there was little change in the number of cases settled in 2009 compared to 2008.

However, the report does highlight an underlying trend: the number of securities law cases has been increasing since 2004, when the rules requiring a plaintiff to prove the extent of damages were eased and the powers of the market regulator –the Securities and Exchange Surveillance Commission – were increased.