Reality attacks Bush's SS plan

WaPo:

A new paper by Yale University economist Robert J. Shiller found that under Bush's default "life-cycle accounts," which shift assets from stocks to bonds over a worker's lifetime, nearly a third of workers would bring in less in benefits than if they remained in the traditional system. That analysis is based on historical rates of return in the United States. Using global rates of return, which Shiller says more closely track future conditions, life-cycle portfolios could be expected to fall short of the traditional system's returns 71 percent of the time.

Both the White House and the Social Security Administration have relied on historical returns in estimating the earnings of proposed personal investment accounts. Shiller used 91 computer simulations to analyze the past performance of stocks and bonds in a variety of portfolios. He measured the returns in 44-year increments, beginning in 1871, to approximate a worker's lifetime contributions to personal accounts.

The results "showed a disappointing outlook for investors in the personal accounts relative to the rhetoric of their promoters," concluded Shiller, a leading researcher in stock market volatility who gained fame in the late 1990s for his warnings of a stock market bubble.

The whole paper is available here.