as of december 31 , 2017 , we primarily leased : 2022 approximately 61000 macro sites and approximately 18000 distributed antenna system and small cell sites . 2022 approximately 2200 t-mobile and metropcs retail locations , including stores and kiosks ranging in size from approximately 100 square feet to 17000 square feet . 2022 office space totaling approximately 900000 square feet for our corporate headquarters in bellevue , washington . we use these offices for engineering and administrative purposes