The California Public Employees Retirement System (Calpers) has revealed that US corporate disasters such as Enron and WorldCom knocked 1.5 percentage points off its US bond performance in the year to June.

The fund said that it was exposed to $345m (€350m) of losses from holdings in WorldCom bonds and $43m from Enron. It was also hit by the related fall in credit ratings for troubled corporate stocks. The losses help to explain a surprisingly poor performance from US bonds for Calpers last year, which showed a gain of just 5.9% gain, against 8.7% from the benchmark.