As the American work force continues to gray, millions of workers are rewriting the rules of retirement. And in the bargain, many employers are finding that experience trumps youth, according to MLive.com.

Findings from AARP say the number of workers age 50 and older will only increase -- no surprise, as most of 76 million baby boomers enter their 50s and 60s.

It is estimated that in 2012, nearly 20 percent of the work force will be age 55 and older, up from 13 percent in 2000. It also found that 68 percent of workers older than 50 who have not yet retired plan to work into their retirement years or not retire at all.

But, work is not all milk and honey for older employees. Many return to or remain at work because they have no choice. Others struggle to find their way in a fast-changing marketplace.

Graying Work Force — As baby boomers reach their 50s and 60s, they are rewriting rules of retirement.
• 68 percent of workers over at 50 plan to work into retirement years or not retire at all.
• In 1950, nearly half of men 65 and older were still in the labor force. That declined to 16 percent in the early 1980s, edged up to 19 percent and is expected to increase further.
• By 2012, nearly 20 percent of the workforce will be 55 and older, up from 13 percent in 2000.
• By 2030, the U.S. population aged 65 and older is expected to double.
• By 2050, the population 65 and older will reach nearly 87 million.

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