The seventh annual Retirement Confidence Survey shows that only 36% of workers have tried to determine how much they’ll need to save for retirement. And of those that tried, 24% still don’t know.Get a free copy of Get a Ballpark Estimate of Your Retirement Needs from American Savings Council, 2121 K St., NW, Suite 600, Washington, DC 20037; 202-659-0670; {www.asec.org/bpk-comp.htm}.