The retirement savings plan known as 401(k) has grown tremendously since it was introduced in 1978, and now it's estimated that about half of all private sector employees have the plan.
And the plan's popularity has grown by 10% just in the past ten years, which at least one expert says is a sign of spectacular growth.
"We have older workers who are leaving the labor force but didn't take advantage of 401(k)s...and then we have younger people who are coming in and just starting 401(k)s at a much higher rate.," says Bankrate Financial Analyst Stephen Kates.
One of the reasons for the increased popularity is the new batch of "automated savings" programs used by many employers, which defaults new employees into the company's retirement savings plan, the majority of which are 401(k)s.
But there is enthusiasm for the plan too, especially among those in Generation X and Millennials, he says.
"About 70% of workers have access to them and about 50% are participating. That's been a pretty persistent gap of about 15 to 20 percentage points between the access and the participation rates.
"So I think that in the future there will be a higher percentage of people in 401(k)s, and a higher percentage of people in 401(k)s in 5, 10, 15 years than we have today," he added.
Most notably, "If you look at people between the age of 35 and about 54 or 55, those people participate at about 60%. It's the people at either end, older and younger, who choose not to participate overall.
And Kates offers this knowledgeable observation about the growing 401(k) trend: "This participation rate is also a great indication of how important Social Security is to this country.
"Because people who do not have 401(k)s or other retirement assets at all, they desperately need some kind of backstop and Social Security for the most part is that.
"There's a lot of data that shows Social Security in old age is one of the biggest things that keeps older adults out of poverty."