Around 97% of all metropolitan areas in the United States have insufficient open space, according to a new study published in the Journal of the Association of Environmental and Resource Economists. In the paper "Open Space in U.S. Urban Areas: Where Might There Be Too Much or Too Little of a Good Thing?" authors JunJie Wu, Jialing Yu, and Walid Oueslati analyze cities across the U.S. and develop a framework to assess if the amount of open space in an area is socially optimal.