Retirement worries aren’t confined to the elderly.

Every generation of working Americans is expressing unease about their retirement prospects, according to a survey from the Transamerica Center for Retirement Studies, a Los Angeles-based nonprofit.

Baby boomers, Generation Xers and millennials felt like they were behind in their retirement savings—and reported account balances low enough to justify their fears, according to the 17th Annual Transamerica Retirement Survey released last week. 

Forty-five percent of the baby boomers—those born between 1946 and 1964—said that they expect a decrease in their standard of living when they retire. 

The U.S. median household savings among baby boomers is around $147,000, according to Transamerica.

Eighty-seven percent of baby boomers believe that Social Security will be a source of retirement income, with 34 percent expecting it to be their primary source of income.

Baby boomers also expect to derive income from their retirement accounts—78 percent of baby boomers said that they expect income from a 401(k), 403(b) or IRA, while just 33 percent expect income from a traditional pension plan.

Eighty-three percent of Generation Xers said that their generation will have a more difficult time achieving financial security than their parents did. Transamerica defines Generation X as those born between 1964 and 1978.

The median total household retirement savings for Generation X is around $69,000—Gen X respondents reported starting to save for retirement at a median age of 28 and contribute a median of 7 percent of their annual pay to their retirement accounts.

Generation X has sapped much of its own retirement prospects: 30 percent of Generation X retirement plan participants have taken a loan or early withdrawal from their retirement accounts, according to the survey. As a result, just 12 percent of the Gen X respondents said they were confident that they would be able to fully retire with a comfortable lifestyle.

Very few millennials, 18 percent, felt “confident” about their retirement prospects. Transamerica defines millennials as those born between 1979 and 2000.

Yet the survey uncovers some hope for millennials—72 percent of them have started saving for retirement, and they start saving at a median age of 22.  The total median household savings among millennials is estimated at $31,000.

Millennials suffer from an information gap when compared to most retirement savers, with 72 percent of the millennial respondents agreeing that they don’t know as much as they should about retirement investing. One-quarter of those participating in retirement plans are not sure how they are investing their savings, and another 22 percent say that their savings are invested mostly in bonds, cash, money market funds and other stable investments.

Among the respondents, 61 percent have not fully recovered from the "Great Recession" more than six years after it ended. One-in-five of the respondents are still at their recessionary financial lows. Forty-one percent say they have somewhat recovered, 13 percent say they have not begun to recover at all and 7 percent believe they may never recover.

Just half of the respondents, 51 percent, felt like they were building a large enough retirement nest egg—and 65 percent of respondents believed they could work until age 65 and never save enough to meet their retirement needs.

Seventy-seven percent of U.S. workers believe Social Security won’t be there when they’re ready to retire.

Harris Poll conducted the study between April 11 and May 12, surveying 4,161 full-time and part-time U.S. workers.