Despite recent studies that paint a rosy picture of how well baby boomers are prepared for retirement, a study from Barclays Global Investors paints a gloomier scenario. Some of the results, which will be published in full in the fall issue of The Journal of Investing, are being released in Barclays' InvestmentInsights.

   The authors, who say optimistic conclusions for the retirement health of baby boomers are based on erroneous assumptions, have titled their analysis as a warning-The Future Shock of Retirement. Jonathan Cohen, Barclays Global Investors senior fixed income strategist; Matthew H. Scanlan, head of American Institutional business; and Matthew O'Hara, head of securitized credit research, say changes are needed by government, employers and individuals to avert a retirement crisis.

   They say errors in some recent studies occur because the researchers assume current costs and benefits will remain stable in the future. Instead, "current benefit levels (for Social Security and Medicare) are unsustainable," the authors say. "Today, 6.9% of federal income taxes go toward the two programs. By 2020, as much as 26.6% of all federal income taxes would be required to sustain current Social Security and Medicare benefits for the greatly expanded retiree population."

   Defined contribution (DC) pension plans now outnumber defined benefit (DB), a trend that won't be reversed, and "DC plans typically fail to address longevity and inflation risk." At the same time, pre-retirees are saving less compared to 10 and 20 years ago and compared to people in countries such as Germany and Japan.

   The wealthiest top half of pre-retirees "look reasonably well prepared for retirement under current conditions, but are highly sensitive to future changes," the trio concludes.