If you’re wondering how much of a Social Security payout you may receive, one number to keep in mind is 35.

Your benefit is based on your 35 highest years of earnings. If you work less than 35 years, the calculation uses zero for your annual income in the years you’re short. Here is an article that provides a description of how Social Security benefits are calculated.

Social Security benefits were established during the Great Depression to help ensure Americans would not retire in poverty. However, they’re not meant to be the “end-all” retirement income plan.

A common mistake in retirement planning is underestimating your life expectancy — maybe based on your parents’ or grandparents’ age — and not saving as much as you need. However, it’s more likely for people to live longer than previous generations, and also have higher medical bills. Even if one spouse dies young, it doesn’t mean the other won’t live late into their 90s.

Women who took time out of the workforce to care for dependents can be particularly vulnerable during retirement. One recent study found that, in a 10-year break early in their career, the shortage of contributions to Social Security and a retirement plan could result in a loss of up to $1.3 million in retirement savings.

You also should consider the impact of inflation throughout retirement. Even though the inflation rate has been low in recent years, it can still make an impact over the long term.  Lastly, make sure that you understand the investment fees associated with your retirement account, as they can have a tremendous impact.