More Americans have increased their retirement savings this year, but the percentage that didn’t contribute at all was unchanged, according to a new Bankrate.com report.

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The study, based on a telephone poll of 1,002 adults conducted by Princeton Survey Research Associational International, found that 23% of working American increased retirement saving contributions — the highest reading in six years — while 16% reduced them and 5% didn’t contribute this year or last. Still, that 5% is half of what it was in 2015. About half of most respondents did not adjust contributions.

“Working Americans are increasing their retirement savings more and more as the economic recovery continues, whether by saving the same percentage of higher earnings or a higher percentage of the same earnings,” said Bankrate.com’s chief financial analyst, Greg McBride. 

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Bankrate’s Finacial Security Index also reflected more optimism about American’s personal finances, rising to 105.8 in August, the third highest reading ever.

The firm’s retirement report broke down contributions by age and by earnings.

Millennials led the way, with 27% increasing contributions over the past year followed by baby boomers (21% contributed more) and Gen Xers (20%). Even more members of the so-called silent generation, which the Pew Research Center defines as born between 1928 and 1945 (too young to fight in World War II) increased retirement savings (13%). But only millennials and baby boomers accelerated their increase in retirement contributions compared to their increases the previous year.

A stronger job market and auto-enrollment in many company retirement plans are helping millennials save more while a steady economy is supporting retirement savings of older workers, according to the Bankrate report.

“The higher propensity among millennials to save speaks to the efficacy of auto enrollment and auto-escalation in many 401(k) plans,” says McBride. Such plan capabilities “not only increase the likelihood of people saving but the amount people are saving.”

McBride noted that since millennials are just coming into the workforce they’re the employees most likely to be taking advantage of these new 401(K) plan defaults.

Millennials are also well increasingly aware that living longer, with rising health care costs and uncertainies about the future of Social Security and Medicare, means “they’re going have to work at it, saving early and saving often,” says McBride.

In general, about half of the survey’s respondents across all demographic age groups except the eldest indicated little change in their retirement contributions this year compared with last year. Forty-five percent of members of the silent generation reduced their contributions, which isn’t surprising. Most are retired and withdrawing funds from retirement accounts rather than increasing them.

Less than 20% of respondents in all other age groups reduced retirement contributions.

Looking at income levels, the survey also found that households earning more than $57,000 a year were most likely to have increased their retirement savings contributions (27%) compared to those earning less than that (28%).

Households earning less than $30,000 annually ($24,600 is the national poverty level for a family of four) were more likely to reduce their contributions (22%) rather than increase them (20%).

Part-time workers were nearly twice as likely to cut contributions (33%) than increase them. A key reason may be that they lack access to employer-sponsored retirement plans, according to Bankrate.com.

Those workers had access to the myRA plan, created under the Obama administration to encourage low- and moderate-income households to save for retirement, but the Trump administration has announced it’s closing down the program.

Also, the current Congress earlier this year repealed an Obama-era rule that eased the way for states to create their own retirement savings plans to cover workers who don’t have access to such plans at work. States can still set up such plans, but they will no longer be exempt from certain requirements of the Employee Retirement Income Security Act.

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