Employment in the construction industry increased in 40 states and the District of Columbia for the year ending in May 2015, according to Associated General Contractors of America.

California and Idaho led the nation in construction industry jobs-gain categories during the 12-month period that ended in May 2015.

Ohio lost the highest number of construction jobs, 4,300, during the same time frame, while West Virginia lost the most jobs on a percentage basis, 12.3 percent, equal to 4,200 jobs, according to Associated General Contractors of America. Other states with high percentages of job losses included Mississippi, minus 7.2 percent or 3,600 jobs; and Rhode Island, minus 5.4 percent, or 900 jobs.

Overall, construction employment increased in 40 states and the District of Columbia from year-to-year, while 28 states and the D.C. added jobs from April to May 2015.

California's construction industry grew by 46,600 jobs for the one-year period, the best of any state in the U.S.

Other states recording high numbers of new construction jobs in the 12-month period include: Florida (28,200); Texas (20,300); Washington (18,100); and North Carolina (15,600).

Idaho recorded the highest percentage of new construction jobs for the year, 11.8 percent, equal to 4,200 jobs. "Construction has outpaced the overall economy in adding workers nationally, but the mix of states with construction job gains keeps changing," said Ken Simonson, the association's chief economist. "The top 10 states for job gains from April to May had previously lagged in adding construction workers, while energy-producing and other states that had record construction employment a few months ago have slipped."

The six states that added the highest percentage of construction workers in May 2015 were all in the Northeast, Simonson noted. This region has seen less growth in construction in recent years than other parts of the country.