If retirement were to last only five years, boomers could feel much more secure. Fifteen years or more, and less than a quarter of them think they will be able to live comfortably.

Older boomers – those who are between the ages of 50 and 64 – with defined benefit plans are much more confident about their retirement than those with defined contribution plans. But that level of confidence for those with either plan is still not nearly as high as it was two years ago.

A survey released Tuesday by consulting firm Watson Wyatt found the percent of workers aged 50 to 64 who are very confident about having enough resources to live comfortably five years into retirement dropped to 44 percent from 63 percent in 2007.

However the level of comfort varies based on time. Five years beyond retirement, 55 percent of workers with DB plans are very confident of having enough resources to live comfortably – 38 percent of those with only DC plans say the same. When looking at 15 years out, only 26 percent of workers with DB plans remain very confident, nearly double the level of workers with DC-only plans (14 percent). And, 25 years out, the numbers drop even more significantly.

As for the overall age group, beyond 15 years into retirement, less than 20 percent think they will have sufficient resources to live comfortably. That percentage was at 34 percent in 2007.

“It’s not surprising that DB plans offer workers more confidence, but fewer workers will be covered by them in the years ahead,” said Jamie Knopping, senior retirement consultant at Watson Wyatt. “The pendulum is swinging toward 401(k)-only environments right now, but if employers find workers’ lack of retirement security creates issues relating to workforce transitions and reduced productivity, it may swing back to a middle ground. Account-based cash balance plans, for instance, offer features of both DB and DC plans, yet do not pose the same level of risk or cost for employers.”