They are using this data for Cost of Living according to the Hired article this article is summarizing.
hired article: https://hired.com/state-of-salaries-2017
cost of living data comes from here: https://www.numbeo.com/cost-of-living/
hired article: https://hired.com/state-of-salaries-2017
cost of living data comes from here: https://www.numbeo.com/cost-of-living/