Some states are better for retirement than others. But even within one state, there is a best county for retirement and a worst. Fortunately 24/7 Wall St. has put together the data to come up with one county in each state that it says is the best place to retire within that state. If you're in the throes of planning your retirement, you know that location can make a difference in the quality of your retirement, and trying to make a decision. And you're not alone. According to 24/7 Wall St., not only are boomers entering retirement in record numbers—National Institute on Aging figures put the number of boomers retiring at a rate of 10,000 people per day—but by 2030, 20 percent of the U.S. population will consist of elderly Americans. That's up from 15 percent in 2015. In reaching its 24/7 Wall St. created an index of 17 health and economic factors in U.S. counties and areas considered equivalent to counties by the U.S. Census Bureau, including parishes and boroughs. It writes, "Only counties where the 65-and-over population grew at least as fast as the nation and was larger than the national average were considered." Money wasn't the only consideration in their evaluation, of course. Health needs drive choice too, so among the factors they considered were the number of medical health professionals (dentists, PCP's, mental health professionals, etc.) per capita, the presence of social institutions, and factors that promote healthier living (diabetes prevalence, access to exercise opportunities, etc.). Data on health measures, it says, came from the County Health Rankings & Roadmaps, a Robert Wood Johnson Foundation and University of Wisconsin Population Health Institute joint program, and are for the most recent year available. Then there's the economic consideration. Among the elements going into this evaluation were the median home value, the monthly cost of living for two people with no children, and the state-local tax burden as a share of state income. Tax burden data came from the Tax Foundation and are for 2012, the most recent year available, while median home value came from the 2017 ACS 5-Year estimates and the monthly cost of living came from the Economic Policy Institute for 2017. All factors were weighted equally. Their listing is in alphabetical order by state, not arranged by a single criterion or a compilation of factors that compare "best" counties to each other. So we've arbitrarily chosen one factor to determine what could be the 5 best counties in the country. Your results may vary, based on your personal needs and desires (perhaps the presence of trout fishing, hang gliding or grandchildren), but since cash can be the determining factor in so many situations we based our top 5 choices on just that: the estimated monthly living expenses for a family of two. See our selection in the slides above. READ MORE: Top 11 best states for retirement on a fixed income 7 best states in the East for retirement 5 worst, best states for pension funding