Abstract
This data article provides a description of the labor market concentration dataset. Using the job vacancy data from Lightcast from 2007Q1 to 2021Q2 (2008 and 2009 data are not available), we measure labor market concentration by using Herfindahl-Hirschman Index (HHI) in labor markets defined at the occupation (six-digit SOC), commuting zone, and quarterly level. The HHI is calculated based on the share of vacancies among all the firms that post vacancies in that market. Data includes information on year-quarter, six-digit SOC, commuting zone, lower bound HHI, and higher bound HHI. Given the growing literature on labor monopsony power, this labor market concentration data can be used by researchers in various contexts, aiming to investigate the impact of employer market power on different labor market and social outcomes.