Members of Generation X and Y appear to be saving for retirement more aggressively than their parents and grandparents, says a new survey released by TD Ameritrade Holding Corp.

Despite a turbulent stock market and shaky economy, investors as a whole made steady progress toward their long-term financial goals in 2011, the survey indicated. However, it also revealed that many older Americans are missing out on opportunities that could position them for further success.

According to the survey, 85 percent have at least an individual retirement account (IRA) or an employer-sponsored retirement plan, either a 401(k) or 403(b) plan. More than a third (36 percent) have both. Four generations participated in the survey: individuals TD called matures, those born from 1930 through 1945; baby boomers, born from 1946 through 1964; Gen X, born from 1965 through 1976; and  Gen Y, born from 1977 through 1989.

The survey found younger workers are more diligently about saving, with 25 percent of Gen Y and 23 percent of Gen X funding both their 401(k) or 403(b) plans and their IRAs, compared with only 16 percent of boomers and 9 percent of matures. Nearly three quarters of boomers surveyed say they're not completely confident that they will reach their savings goal by the time they are ready to retire.

Maritz Inc. conducted the telephone survey for TD Ameritrade and questioned 1,509 adults between 22 and 81 years old from July 20 through August 17. Among these respondents, 854 are working full time or part time.

Carrie Braxdale, managing director of investor services for TD Ameritrade Inc., a broker-dealer subsidiary of the holding company, said the survey shows many working Americans, especially those in the younger age bracket, are taking advantage of saving for retirement in a tax-free environment through options like an IRA, despite a tough economy.

Braxdale said many boomers, those who are 50 and older, are missing out on catch-up contributions, which let them contribute an additional $5,500 to an employer-sponsored retirement plan. More than two-thirds (68 percent) are not taking advantage, with half skipping them because they can't afford them. However, another 21 percent said they had never heard of catch up contributions.