The volume of U.S. hotel rooms under construction decreased year over year for a ninth consecutive month, according to CoStar’s September 2025 data. CoStar is a leading provider of online real estate marketplaces, information and analytics in the property markets.The volume of U.S. hotel rooms under construction decreased year over year for a ninth consecutive month, according to CoStar’s September 2025 data. CoStar is a leading provider of online real estate marketplaces, information and analytics in the property markets.