In May 2014, there were 2,687,310 employed registered nurses in the United States, more than any other healthcare occupation. Nationwide, registered nurses accounted for nearly 2 of out every 100 employed persons. Some metropolitan areas have a higher concentration of employment in this occupation than other areas. We measure this concentration with the location quotient. A location quotient greater than 1 means the occupation has a higher share of area employment than the national average….