More than one-third of workers have never increased the percentage of salary they contribute to their retirement plan.

More than one-third of Americans who contribute to an employer-sponsored retirement plan have never increased the percentage of their salary they contribute to their company’s plan, according to new research.

TIAA-CREF discloses this finding in an online survey of 1,000 adults, ages 18 years and older, who contribute to an employer-sponsored retirement plan. The survey was conducted by the independent research KRC Research.

The survey reveals that 36 percent of working Americans have never increased the percentage of salary they contribute to their retirement plan. And an additional 26 percent of workers have not increased their contribution in more than one year. “Considering that 44 percent of American employees save 10 percent or less of their annual income each year, these findings indicate that many employees have the opportunity to improve their retirement readiness by increasing their plan contributions regularly,” the report states.

More than half (53 percent) of employees with company retirement plans were not automatically enrolled in their companies’ plans. Nearly four in 10 respondents (37 percent) who were not automatically enrolled in a plan reporting that they waited six months or longer to enroll. And one in four employees (24 percent) waited a year or more.

The survey also finds that 57 percent of workers did not increase their plan contribution after their last raise. The most common reason cited for not increasing contributions after a raise was an immediate need to pay expenses.

One-quarter (25 percent) of respondents say they did not increase their contributions after their last raise because they were already contributing the maximum amount to their retirement plan, although men (33 percent) were nearly twice as likely as women (17 percent) to be contributing the maximum amount allowed.

Millennials (age 18-34) are more likely than any other age group to increase savings after a raise (52 percent). Of those Millennials who did not increase savings after a raise, 23 percent did not do so because they were already contributing the maximum amount allowed.

The survey also finds that respondents are not reallocating their investments appropriately as they age. One-quarter (25 percent) of workers have never made changes to how their money is invested. And an additional 28 percent have not made changes to how their money is invested in more than one year.

Millennials again were significantly more likely to have changed how their money was invested in the past year compared to those 35 years or older (59 percent vs. 42 percent).

One-third (34 percent) of those age 55 or older say they have never made a change to the way their money is invested. Upshot: They are less likely to have taken the steps necessary to transition from saving for retirement to creating income to last for a lifetime.  

Read an executive summary of the report here.