Twenty-five percent of Americans across all age groups admit they are not saving at all for retirement, or are unsure, according to a new survey. 

The Country Financial Security Index found that 38 percent of those 40 and older said they regret decisions they have made with their retirement savings, with 47 percent of them admitting they did not start to save early enough. Nearly half (46 percent) of the survey respondents said it is not possible for a typical middle-income family to save for a secure retirement.

“It’s a real wake-up call to see that so many Americans are not putting money towards their nest egg and are, in turn, generally concerned about retirement prospects,” said Country Financial director of wealth management Troy Frerichs in a statement. “My advice to those Americans who haven’t begun saving, and to those who have is save early and save often. Making retirement a priority is an important step in achieving long-term financial security and avoiding what appears to be the coming retirement crisis.”

A 55 percent majority of those surveyed said they either are not participating in a 401(k) plan or do not know. While 29 percent said a 401(k) is the primary way they are saving, most lack a diversified retirement portfolio as just 17 percent said they are using at least two different savings vehicles. Of the 45 percent who do have a 401(k), 30 percent do not know where their contributions are invested. However, 43 percent of the survey respondents said they check the health of their retirement savings every few months.

Twenty and thirty-somethings were more pessimistic about their retirement prospects than older respondents. Thirty-two percent of the respondents between the ages of 18 to 29 are not saving for retirement or are not sure, more than any other age group. More adults ages 30 to 39 said it’s not possible for a typical middle-income family to save for a secure retirement than any other age group (47 percent). Of the 44 percent of 18 to 29 year-olds who do participate in a 401(k) plan, 39 percent said they do not know where their contributions are invested.