Early and late baby boomers should be treated as separate generations because their attitudes towards finances and retirement differ so much, says the Insured Retirement Institute.

The Great Divide: Financial Comparison of Early and Late Boomers’ Retirement Preparedness, a study released by the institute today, divided boomers into two groups: boomers between the ages of 61 to 66 and those between 50 and 55. Researchers interviewed 802 individuals for the study.

The older group worked many years in a stable economic atmosphere at a time when defined benefit pension plans were still in place, IRI notes. Late boomers had their early working years in a more unsettled economic time, when defined contribution plans came into play.

Boomers differ in their confidence level for retirement, according to the study. Older boomers are more optimistic, with 42 percent believing they have enough savings to live comfortably throughout retirement. Only 25 percent of younger boomers shared this confidence.

But older boomers are less confident about their financial situation improving. One quarter of older boomers think their personal financial situation will improve in five years while 41 percent of younger boomers feel that way. About half of both groups (48 percent of older boomers and 41 percent of younger boomers) think their personal finances will be about the same in five years.

While savings are lagging for both groups, according to IRI, 32 percent of older boomers have less than $100,000 saved for retirement, while 47 percent of younger boomers report the same.

Thirty-six percent of older boomers identify a defined contribution plan as a major source of retirement income, compared to 43 percent of younger boomers.

The most common reason for uncertainty about when they will retire for older boomers is that they say they enjoy working (20 percent), while for younger boomers, the most common reason for the uncertainty about when they will retire is that they do not have enough savings (27 percent).

At the same time, many older boomers have already retired and only 43 percent remain in the workforce, compared to 80 percent of younger boomers who are still working.

For older boomers, 20 percent are struggling to pay their mortgage or rent, compared to 31 percent of late boomers.