Where you retire can have an effect on whether you're comfortable or stressed about money. But the destinations that are most friendly to retirees and provide them with an actually livable living standard might not be the ones you expect, according to a post on the Squared Away Blog at the Center for Retirement Research at Boston College. In fact, it cites a 50-state analysis by the University of Massachusetts' Gerontology Institute in Boston that compares the actual relationship between a state's cost of living and a retiree's income. It identifies the gap some retirees fall in, where their income is above poverty level but not enough to help them be economically secure. Interestingly, the study finds that there are more retirees stuck in this gap than there are retirees living below the poverty level. Says the study, "On average throughout the United States, the share of older adults living alone with incomes below the FPL [federal poverty level] is 18.2 percent; another 32.1 percent live above the poverty level yet still have income less than what is required to live with economic security." It might surprise you to learn that even some of the poorest states with the lowest costs of living can end up with a large percentage of retirees that fall into this gap—since incomes in those states often aren't high enough even to meet a low cost of living. In fact, some states with the lowest cost of living keep company with states with the highest cost of living, since even if salaries are high, pensions and Social Security checks might not be able to keep up. In the gallery above we've highlighted the five states with the highest percentage of "gap" retiree couples and the five with the lowest, based on the "Elder Index" formulated by the Gerontology Institute at the University of Massachusetts Boston in collaboration with Wider Opportunities for Women and a national Advisory Board. The Elder Index defines economic security as "the income level at which older people are able to cover basic and necessary living expenses and age in their homes, without relying on means-tested income support programs, loans or gifts." We've also highlighted the five most expensive and five least expensive states for retirement according to Bankrate's evaluation, which instead calculates its standings through different criteria: affordability, crime, culture, weather, wellness, average home costs and regional price parity. You'll find there's a substantial difference in the rankings. READ MORE:

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