How do you know if you're on track for a financially secure retirement? There are a zillion ways to find an answer to that question, but in a time of financial and economic uncertainty perhaps the simpler the method the better. Brett Hammond, TIAA-CREF's chief investment strategist, has designed an easy way for employees to check on retirement readiness based on their asset-to-salary ratios at different points in their career. "The big problem is that there is no magic number for the amount of money you need," Hammond says. "This is an attempt to address the needs of real people. If you tell me your assets, income, and age, I can tell if you're on track for retirement."

How will you know if your nest egg will cover 60% of pre-retirement income once you stop working?

If you're 35 and plan to retire at 65, you need 2.1 times your salary to be on track. By 45, you had better have 3.6 times. At 55, the multiple rises to 5.4 times. And by the time you retire, you'll want it to be 7.7 times.

BusinessWeek.com provides the TIAA-CREF retirement formula.