The study, published in the February 2004 EBRI Notes, also found that the number of Americans making deductible contributions to IRAs has dropped steadily since 1990.

By contrast, the number contributing annually to Keogh accounts, which offer tax-sheltered retirement savings for the self-employed, has grown steadily. The number of such contributions rose by more than 50 percent between 1990 and 2001 and more than $13 billion was deposited to such accounts in 2001. Taxpayers deposited an added $7.4 billion in deductible contributions to IRA accounts that year.

At the start of the period, IRA contributions outnumbered Keoghs by more than six to one. By the end, there were less than three IRA contributions per Keogh. During this period, Roth IRAs, which are not tax deductible, but instead allow accrual of untaxed gains, were introduced. However, a downward trend in deductible contributions to IRAs started before their introduction.

IRA assets grew steadily every year from 1981 to 2000, when the downturn began. Subsequently, the percentage of assets in banking institutions grew from 9.2 percent (in 1999) to 11.3 percent (in 2002) while the percentage held by insurance firms rose from 9.3 percent to 10.7 percent. The percentage in mutual funds and brokerage accounts declined, largely because of failing markets, but these options continue to include most assets.

"These figures will help inform the debate when Congress considers administration proposals to eliminate the IRA program and replace it with new individual savings vehicles like Lifetime Savings Accounts and Retirement Savings Accounts, " said Dallas Salisbury, EBRI president and CEO.