The AHS asks whether vacant or "usual residence elsewhere (URE)" units are held for recreational purposes. Data for seasonal and vacant units is available in the AHS Table Creator. In the Table Creator, the “Occupancy/Vacancy Status” column variable can be selected with this table. The working paper, "Multiple-Home Ownership and the Income Elasticity of Housing Demand", from the Joint Center for Housing Studies at Harvard University discusses the differences in elasticity of demand between homeowners with and without second homes.