That means the future may turn up more people such as Bob Rainey, 73, who works three days a week at Vanguard Group in Malvern, speaking to callers about their mutual-fund investments.
"I always wanted to learn a little about the financial world," said Rainey, who took securities license exams to qualify for the job. "I'm kind of enjoying it. I talk to people and help them at the same time."
The Elverson resident said he took the Vanguard post at age 65, soon after retiring from a long career at AMP Products Corp., where he served as marketing manager.
Overall, more than 70 percent of the workers surveyed in the Rutgers study said they would work after retiring from full-time employment, even if they had enough money to live comfortably for the rest of their lives.
The researchers randomly phoned 1,005 workers across the country in August, and questioned them on their attitudes about work, employers and government. The study was codirected by the University of Connecticut's Center for Survey Research and Analysis.
Respondents tended to show surprisingly positive attitudes toward extended work lives, according to Van Horn:
About 42 percent said that, after retiring, they would like to work part-time for enjoyment, while 10 percent said they would seek part-time employment for the income.
About 19 percent said they would like to start their own businesses when they retired, and 11 percent stated they hoped to spend their free time volunteering.
About 3 percent said they wanted to work full-time for income, but in a different job, while 5 percent were undecided.
The availability of indoor "new economy" jobs could be one reason for rosier perceptions of work after retirement. "Work used to be more physically demanding than it is today," Van Horn said. "People's bodies were really spent in heavy manufacturing and physical labor."
New surgical techniques and medicines have not only have led to longer life expectancies, but have also meant improved health and productivity during those later years, Van Horn said.
Therefore, baby boomers and others will increasingly view retirement "not as a cliff they want to jump off, but as a time to gradually phase out of work," he said.
Despite a willingness to work extra years, most of the survey's respondents, especially younger ones, said they wanted to retire early from their full-time jobs, perhaps to embark on something a little more interesting or fulfilling.
About 40 percent of Generation X workers, defined as between the ages of 18 and 34, reported they would prefer to retire before the age of 50, according to the Rutgers study. About 10 percent of baby boomers, or workers age 35 to 54, also reported a preference for retiring before age 50.
But whether today's workers will actually be able to afford such early retirements is another question. Many respondents admitted there were gaps between their dreams and expectations.
In fact, of the respondents whose ideal retirement age was under age 55, about half predicted they would not be able to afford retirement until much later. Only 29 percent of all respondents said they were very confident that they would be able to retire when they wanted, while 24 percent said they had not begun to plan for retirement or were not confident they would be able to retire at their ideal age.
Women were less likely than men to express confidence that they would be able to retire at a young age. About 30 percent of women said they believed they would not be able to retire until age 61 to 65, compared with 22 percent of men.
Dreams of landing fulfilling part-time jobs or of starting businesses after retirement may also fall short for many, said Sara Rix, a senior policy adviser for AARP, formerly called the American Association of Retired Persons.
That is because most part-time jobs available are "not particularly desirable," Rix said. "They are lower-wage jobs with lower benefits and are often physically demanding."
But she added that employers could improve the quality of part-time work in coming years if they put their minds to it. One way would be to introduce phased retirement plans for aging workers.
"Society and workers stand to benefit from longer voluntary worklife," Rix said.
Roger Lane, for one, is enjoying his busy post-retirement days. He retired last year at age 65 as a Haverford College professor and historian, and now spends his time working on a social history of ordinary life in the 20th century. He can also be found giving speeches (including one this week at the former Eastern State Penitentiary before a group of Philadelphia judges), and teaching an occasional class at the college.
"I teach when I feel I have a need for a captive audience," said Lane, the author of Murder in America. "I don't have to go to faculty meetings, department meetings, or committee meetings."