The rap against older workers — that they are expensive, unimaginative and afraid of technology — may be shifting as businesses feel the pinch of a tighter labor market.

Retiring baby boomers are exiting the workforce at a faster clip than the younger generations can replace them. While some sectors of health care and manufacturing already are struggling to fill jobs, demographers say the brunt of the labor shortage will strike businesses in Minnesota and the nation just a few years from now, between 2020 and 2025.

A new lexicon is emerging among hiring managers, whose focus has traditionally been on recruiting and retaining younger employees to build the future workplace. Some now are talking about extending the work "life cycle" to help older workers stay on the job longer and to convince experienced retirees to return to work.

"We're basically sitting on a gold mine of people who are in the prime years of life — of thinking, creativity, ingenuity, resourcefulness — that we really should tap," said Kari Benson, executive director of the Minnesota Board on Aging.

Yet attitudes about workers 55 and older don't always reflect that sentiment. Numerous studies have found that employers resist hiring or investing in older workers for fear that they are less engaged, don't adapt well to change or will have higher medical costs.

With immigration rules tightening, the need for qualified workers — of any age — is beginning to alter those perceptions. Some employers are taking a fresh look at values older workers bring to the job, such as experience, loyalty, leadership and professionalism.

Michael Rossman, Hennepin County's chief human resources officer, said understanding the needs of older workers is the topic du jour among his industry peers.

"It's what everyone's dealing with," he said. "The workplace is changing faster than most people can adapt."

Rossman and nearly 300 other top managers and supervisors at Hennepin County recently took part in a University of Minnesota study by graduate students aimed at measuring perceptions of their baby boomer workers, and assessing the role this cohort might play to bridge the workforce gap.

The report, released earlier this month by the Minnesota Board on Aging, found that Hennepin County's government workforce of about 8,000 skews older than the state as a whole. About a third of the county's public sector workers are older than 55, compared with 19 percent of workers statewide.

With a diverse range of jobs to fill — such as public works, IT, law enforcement, libraries, health care and social work — on top of stiff competition for workers from the higher-paying private sector, Rossman said many departments are discussing ways to keep an aging workforce committed and productive.

Some baby boomers want to scale back their hours yet not lose benefits. Others value added flexibility to care for an aging spouse or parents. Perhaps an older worker needs to transition to a desk job after a career working in the field but don't see a path to do so. And many others of retirement age simply don't have enough money saved and need to draw a paycheck as long as they can.

"Not everybody wants to retire," Rossman said. "The good news is that a lot of the same things we're doing to attract and retain a sustainable workforce of the future, are some of the same things that will retain and return older workers to the workforce."

Nationwide, about 68 percent of baby boomers, who now are aged 54 to 72, are still in the labor force, according to U.S. Census data. But by 2030, in a little more than a decade, the youngest of the boomers will turn 65, an age when retirement seems doable because Medicare provides a safety net of health insurance.

Decisions by this massive cohort about whether and when to retire will have a profound impact on the job market, Social Security spending and funding of other government programs should their savings run out in old age.

The study argued that programs aimed at training workers won't be enough to satisfy the state's need for workers between 2020 and 2030. New policy directives and incentives may be needed, including offering pathways for baby boomers to delay retirement, drawing in workers from other states and supporting immigration from other countries

"There's all this focus on workforce development, but none of it is guided to older workers," said Mary Jo Schifsky, whose business, GenSync, advocates for meaningful career pathways for older adults and who helped initiate the study for the Board on Aging with the U's Humphrey School of Public Affairs. "We need career pathways for older workers just as much as we do for younger workers."

In the U survey, managers ranked baby boomers high on loyalty, professionalism, engagement and their commitment to producing quality work.

Results were mixed regarding older workers' ability to learn and apply new skills.

Half of the managers 53 and older said younger workers were better at learning new skills, yet the other half believed workers of all ages were equally adept. The discrepancy, according to the report, highlights a need to tailor training approaches to different generations of workers.

Perhaps most pressing for Hennepin County is that 40 percent of its workers will hit retirement age in the next three years.

The loss will disproportionately hit the top ranks of leadership, where 53 percent of directors and about a third of its managers will be eligible for retirement within five years.

Rossman said that while it's vital to hire and develop young talent, losing veteran county workers could have immediate and lasting consequences for the public that relies on county services.

"The knowledge transfer in an organization is one of the biggest drains and has the worst impact on organizations when people retire or leave," he said. "And it's not done very well, even in places where people are trying really hard. It has a lot of impact on the customer."

Benson, the state's aging director, said the report has value beyond the county's experience. She said it will help inform priorities related to older workers' employment, civic participation and community engagement as her agency works to prepare the state for the coming age boom.

Even more, she hopes it will begin to pierce outdated ideas.

"Jumping to the assumption that an older worker needs to get out of the way because they are not being innovative or engaged anymore because of their age is so shortsighted and ageist," Benson said. "It very much could be a number of other things: they are bored, because maybe they have been doing something for 20 years. Just having the conversation and allowing for flexibility to keep them contributing to the organization could make all the difference."

Jackie Crosby • 612-673-7335 Twitter: @jackiecrosby