12a. Union membership and coverage in construction and other industries, 2015 and 2016
12b. Union membership and coverage in construction, public vs 12b. Union membership and coverage in construction, public vs. private sector, 2015 and 2016
12c. Union membership, selected construction occupations, 2015 (Wage-and-salary workers)
12d. Subject Matter Experts ratings for each union for each sector
12e. Union market share for the Heavy Civil/Industrial sector, 2005-2012
12f. Percentage of construction workers who are union members, by state, 2013-2015 average (Wage-and-salary workers)