The study, by the University of Massachusetts Boston and the nonprofit organization Wider Opportunities for Women (WOW), compared income and expenses for people 65 and older in all 50 states and the District of Columbia. In every state, the median income (half are above, half are below) was less than the Elder Index, a measure the two organizations developed that assesses the actual costs of housing, food, transportation, personal items and health care, taking into account local differences. (The Elder Index excludes government support for basic necessities, including food, utilities and transportation.)

"Growing old in America is getting more and more expensive," said Jo Ann Jenkins, president of AARP Foundation, a charitable organization affiliated with AARP that helps struggling Americans 50 and over move from vulnerability to opportunity. "This report from WOW and the University of Massachusetts Boston confirms what most of us who work with older people see every day — older people are being left behind. This is not the time to cut programs like Social Security and Medicare that provide them with some support — and into which they paid their entire working lives."

Massachusetts has the largest income gap at $10,248 — i.e., the median income of retired people age 65 and older ($16,800) minus the Elder Index ($27,048). It is followed by four other states where the rising cost of living is outpacing the fixed incomes many retirees depend upon: the District of Columbia (gap of $9,988), New York (gap, $9,244), Hawaii ($8,804) and Connecticut $8,020.

While all states have income gaps, the five states with the lowest are Arizona ($2,040), Michigan ($1,860), Utah ($1,824), Montana ($1,354) and Alaska ($1,068).