Some 70 percent of those who own Individual Retirement Accounts plan to defer withdrawals from these accounts as long as possible, according to a new study by the Investment Company Institute. And even more have a strategy on managing their income and assets during retirement.

Only about 40 percent of U.S. households, or 46 million families, own IRAs, the ICI research shows. And less than 15 percent of all U.S. households invested in an IRA in 2006.

Still, IRAs represent more than one-quarter of Americans’ retirement assets and 10 percent of all household financial assets, with $4.6 trillion in assets. “Our research consistently shows that IRA savers are good stewards of their money,” says ICI President and CEO Paul Schott Stevens. “They are looking ahead, making responsible financial plans and shepherding their funds.”

As for withdrawals, fewer than one in five households with traditional IRAs took withdrawals in 2006, according to the ICI. Most of those who did, 62 percent, cited tax rules mandating required minimum distributions for IRA owners at age 70 1/2 .

Janet Levaux is the managing editor of Research; reach her at jlevaux@researchmag.com.