The Chicago City Council passed a "Big Box Living Wage Ordinance" in July 2006, mandating that all retail stores larger than 90,000 square feet and operated by companies making more than $1 billion a year in revenue pay workers a minimum hourly wage of $10 per hour. However, the ordinance was vetoed by Mayor Richard Daley in September 2006, who said the measure would be harmful to the city. Studies have found that the entry of Wal-Mart into a county reduces both average and aggregate earnings of retail workers and reduces the share of retail workers with health coverage on the job. As a result of lower compensation, Wal-Mart workers make greater use of public health and welfare programs compared to their counterparts in other retail industries.