FACTBOX-What is California pension fund Calpers?

(This is part of a special report on risk at Calpers, to see other stories and graphics double click on: [ID:nN2254816])

Oct 23 (Reuters) - The following are some facts about the California Public Employees' Retirement System, Calpers, the largest U.S. public pension fund, which manages assets comparable in value to the gross domestic product of Israel.

* Calpers manages retirement benefits for more than 1.6 million people, around 492,500 of whom are already collecting a pension. It pays defined benefit pensions, based on a member's years of service, age and final salary. Calpers also manages health benefits for nearly 1.3 million members.

* The value of Calpers assets fell a record 23 percent in the year to June 30, 2009, falling to $180.9 billion from $237.1 billion a year earlier. The fund's assets fell as low as $160 billion in March and are currently around $200 billion.

* Members and employers contributed $10.7 billion in the year to June 30, 2009, and the fund paid $11.85 billion in retiree benefits in the year. Nearly four in five retirees (78 percent) receive $36,000 or less a year.

* Calpers members are 31 percent state employees, 38 percent school employees and 31 percent other local public agency workers. They range from judges and legislators to law enforcement and corrections officers, water and parks workers and firefighters.

* Calpers was established in 1932 to provide pensions for state employees. In 1984, voters passed a law allowing Calpers to invest more than 25 percent of its portfolio in stocks.

(Source: Calpers) (Writing by Claudia Parsons)