A new study by the Pew Research Center’s Social & Demographic Trends unit reveals that when it comes to working, U.S. senior citizens aren’t ready to leave the stage. Instead, they’re staying on for encore after encore.

Incredibly, the Pew study forecasts that nearly 95% of the growth of the American labor force over the next eight years will be among workers age 55+.

What’s behind this interesting demographic development – one that has actually been taking shape for some time now? I think it’s three things:

 Americans are living longer and staying healthier longer
 Most seniors wish to stay active and productive as long as possible
 The economic climate

This last factor has been particularly acute with the current recession that has caused the loss of retirement investment balances and real estate values. This is underscored in the Pew survey, where nearly two thirds of workers in their 50s reported that they might need to push back their expected retirement date because of the current economic conditions.

But the Pew study also makes clear that once the recession lifts, it’s highly unlikely that the aging of the workforce will reverse. That’s because many seniors find that working satisfies fundamental social needs like “being with other people” (56%), “feeling useful” (68%), and “giving me something to do” (57%).

By contrast, the other workers surveyed by Pew (ages 16 to 64) see themselves working “to support myself and my family” (88%), “live independently” (78%), and “to qualify for a pension or Social Security” (65%).

All of which proves that as people mature and move through the cycle of life, many of them make a shift in their perspective: “Work to Live” becomes “Live to Work.” For someone just entering the workforce, that might be laughably hard to believe … but the Pew survey results bear it out.

And another takeaway message to younger workers: Don’t expect your older colleagues to exit the scene anytime soon … the competition’s still hot ‘n heavy.