More than 500 current and former government employees packed Fort Collins' Lincoln Center on Monday evening to discuss their pension fund's $11 billion loss and how managers plan to deal with it.

The Colorado Public Employees' Retirement Association lost 26 percent of its assets in 2008 as the stock market tanked. PERA managers said while they did better than the overall stock market, the massive loss has imperiled PERA's long-term sustainability.

"That's a great big negative number," PERA executive director Meredith Williams told the crowd.

PERA is a state-created alternative to Social Security and today has about 435,000 members or recipients. It covers state, judicial branch and school district employees as well as many Colorado State University workers.

PERA today has $31.6 billion in assets, more than enough to pay benefits for years without changes, Williams said.

In addition to the investment losses, PERA has seen more people retire earlier than expected, smaller-than-projected contributions from workers and employers, and higher-than-expected salaries, requiring higher payouts.

"We're not going to invest our way out of it," Williams said.

One option under considering: require still-working PERA members to work longer to receive their full benefits, something Social Security has done.

Today, workers who want to retire early can either take a reduced payment after retiring early or buy credit to get them up to 30

years of service, providing full benefits.

The average age of retirement is 58 years old, with 23.2 years worked, PERA staff said.

Full retirement benefits reached after 30 years equals 75 percent of a worker's three highest-paid years.

Other options: require higher contributions from employers or cut benefits to retirees, which Williams noted might be illegal.

This was the sixth PERA listening meeting hosted by board members who plan to submit a solution to state lawmakers by Nov. 1.

Several speakers said their PERA benefits were part of their employment contract and worried state lawmakers will make ill-considered changes.

"I trust PERA to manage the fund," said retired music teacher Ray Harrison, who drove from Hygiene to hear the panel. "With all due respect, I do not trust the General Assembly."

But former Poudre School District teacher Jim Wade of Fort Collins criticized the board for boasting about losing less money than other funds.

"I've done a much better job (investing my own money) than you have and I'm just an ordinary guy," Wade said. "You've done a terrible job."

Wade's comments drew scattered boos.

PERA officials said the typical retired member receives $2,700 a month, worked for the government for 23 years and is 68.8 years old.