First, your benefits are based, in large measure, on your earnings history. Social Security says that whether you claim early or later, you will get about the same amount of benefits over your lifetime if you live to an average age.

Second, Social Security gives you a choice: Start benefits early and you'll receive more checks but with fewer dollars in each check. Start benefits later and you'll receive fewer checks but with more money in each check. People born in 1943 or later, who delay taking benefits until 70, will get a bonus of 8 percent a year for waiting. (After age 70, the amount will stop increasing.)

In deciding when to take your benefits, think about these questions:

• Your financial situation. Do you need your benefits as soon as you can get them or can you afford to wait and let the monthly amount increase?

• Your health. How long do you expect to live? Did your family members live into their 80s and 90s?

• Your work. Do you expect to continue to work? Years of additional work could raise your lifetime earnings averages and thus increase your Social Security benefits. But if you take benefits at 62 and continue to work, your monthly check will be reduced if your annual earnings exceed a ceiling, currently $14,160 a year. This earnings penalty goes away when you reach your full retirement age.

As you can see, there are many factors to weigh. A new AARP Social Security benefits calculator can help you make your decision.

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Stan Hinden, a former columnist for the Washington Post, wrote How to Retire Happy: The 12 Most Important Decisions You Must Make Before You Retire. Have a question for the Social Security Mailbox? Check out the archive. If you don't find your answer there, send a query.