At 92, Pete Perillo still has a workday routine. He says a prayer and then heads off in uniform to guard the city courthouse.
"In the morning, I talk to St. Anthony and I come in," Perillo said. "I come in every day. ... These people, they keep me alive."
Perillo works as a judicial marshal in Stamford Superior Court's civil division. He carries no gun.
He is one of a growing number of people for whom retirement age has lost its meaning. They are staying on the job longer and longer past that point -- some for personal satisfaction, others out of necessity.
Some are even working away into their 90s and beyond: In Maryland, Grace Wiles, 97, works about 25 hours per week at a shoe repair store. In Nebraska, 98-year-old Sally Gordon is the legislature's assistant sergeant at arms.
They are all younger than Waldo McBurney, a 104-year-old beekeeper from Kansas who was recently declared the US' oldest worker.
About 6.4 percent of Americans 75 or older, or slightly more than 1 million, were working last year. That is up from 4.7 percent, or 634,000, a decade earlier, according to the US Department of Labor.
About 3.4 percent of Americans 80 or older, or 318,000, were in the work force last year, up from 2.7 percent or 188,000 a decade earlier, officials said.
"For the first time in history, four generations are working together," said Melanie Holmes, vice president of corporate affairs for Manpower Inc, an employment services company.
With the first wave of Baby Boomers reaching the traditional retirement age, Manpower has urged companies to start thinking about ways to retain and recruit older workers, through flexible scheduling for example. This will help them fill positions as the labor pool shrinks.
According to Holmes, companies need to extend their diversity training to include age as well as race and gender. Older workers often bring experience and a strong work ethic, but may have a different style of work: They may be better at face-to-face contact than electronic communications, and may adhere more strictly to company rules, Manpower officials said.
Some companies are reluctant to hire older workers. A survey last year by Manpower found that 24 percent of employers viewed expectations for higher salary or stature as one of the top roadblocks to hiring older workers, while 21 percent cited health care costs.
Still, after decades of decline, the number of workers 55 and older began to rise about a decade ago and that trend has accelerated since 2000, labor officials said.
Experts cite several factors for the growth, including people living longer and the Senior Citizens Freedom to Work Act in 2000, which allowed workers 65 through 69 to earn as much money as they want without losing Social Security benefits. Other reasons include the gradual increase in the age for receiving Social Security benefits to 67 and a decline in traditional pensions and retiree health benefits.
The number of older workers is likely to continue to rise as Americans live longer and are unable to make ends meet on Social Security state pensions and savings in company-sponsored retirement plans, said Alicia Munnell, director of the Center for Retirement Research at Boston College.
"It's a concern to me they will end up having to," Munnell said.
Irene Olsen, 95, works 20 hours a week at a senior center in Milford, Connecticut, to pay for rising taxes and utilities.