As the economy collapsed last year, federal retirements dropped to their lowest level in seven years, according to statistics released Monday by the Office of Personnel Management.

OPM said 43,649 full-time permanent employees retired in fiscal 2009 — 27 percent fewer than OPM had projected would retire. Federal retirements haven't been that low since fiscal 2002, when 41,699 employees retired.

"I've never seen that large a difference" between projections and actual numbers, said John Palguta, vice president for policy at the Partnership for Public Service. "But it's important to understand these are deferred, not canceled, retirements. I'll wager that in 2010, we'll see clearly higher retirement numbers."

The sudden decline in retirements is likely due to the poor economy, he said, which has slashed the value of many federal employees' Thrift Savings Plan accounts.

Palguta said that federal managers need to take advantage of the retirement slowdown by implementing programs to capture the institutional knowledge of those employees nearing retirement for the benefit of new recruits.

"This is a time to focus on workforce planning," Palguta said.

OPM said it has not updated its retirement projections since January 2009. Last year, OPM projected that nearly 577,800 employees would retire by the end of fiscal 2018.