Significant gains in U.S. green building are expected in 2018, according to the World Green Building Trends 2016 report from by the U.S. Green Building Council and Dodge Data and Analytics. Last year, about 24 percent of U.S. building firms said more than 60 percent of their projects were green, and 39 percent of survey respondents expect green projects completed by their company will constitute 60 percent or more of their total projects annually by 2018. The main drivers of the U.S. green building sector have been client demands, the industry's conviction in green building, environmental regulations, market demands, and lower operating costs. Builders in the U.S. listed a greater number of incentives than their global counterparts in terms of client demands, operating costs, and the belief that green building is the right course of action. Seventy percent of U.S. green builders cited higher initial costs as one of the top three obstacles to green building growth, along with a lack of market demand and difficulty making a business case because of the division between capital and operating costs. The study found the inability to accurately track the benefits of green building for businesses is another significant barrier in the U.S.