What is the purpose of the Uniform Lifetime Table?

The Uniform Lifetime Table is a life-expectancy chart that helps people with retirement accounts determine their mandatory distributions, states Bankrate. A retiree over 70 1/2 finds his age and the corresponding distribution period, then divides the value of his IRA by the distribution period number to find his minimum distribution.

The table is for IRA owners who are married, have a spouse who is no more than 10 years younger, and owners whose spouses are not the sole beneficiaries of the IRA, states IRS.gov. A beneficiary uses the single life expectancy table, while a spouse who is more than 10 years younger and a sole beneficiary of the IRA use the joint and last survivor expectancy table.