item 2 .properties our principal offices are located in boston , southborough and woburn , massachusetts ; atlanta , georgia ; cary , north carolina ; mexico city , mexico ; and sao paulo , brazil .details of each of these offices are provided below: .
[['location', 'function', 'size ( square feet )', 'property interest'], ['boston ma', 'corporate headquarters us tower division headquarters and american tower international headquarters', '19600', 'leased'], ['southborough ma', 'information technology data center', '13900', 'leased'], ['woburn ma', 'us tower division lease administration site leasing management and broadcast division headquarters', '57800', 'owned ( 1 )'], ['atlanta ga', 'us tower division accounting services headquarters', '21400', 'leased'], ['cary north carolina', 'us tower division new site development site operations and structural engineering services headquarters', '17500', 'leased'], ['mexico city mexico', 'mexico headquarters', '11000', 'leased'], ['sao paulo brazil', 'brazil headquarters', '5200', 'leased']]
( 1 ) the facility in woburn contains a total of 163000 square feet of space .approximately 57100 square feet of space is occupied by our lease administration office and our broadcast division , and we lease the remaining space to unaffiliated tenants .in addition to the principal offices set forth above , we maintain 15 regional area offices in the united states through which we operate our tower leasing and services businesses .we believe that our owned and leased facilities are suitable and adequate to meet our anticipated needs .we have also established an office in delhi , india to pursue business opportunities in india and southeast asia , and we have an international business development group based in london , england .our interests in our communications sites are comprised of a variety of ownership interests , including leases created by long-term ground lease agreements , easements , licenses or rights-of-way granted by government entities .pursuant to the loan agreement for the securitization , the tower sites subject to the securitization are subject to mortgages , deeds of trust and deeds to secure the loan .a typical tower site consists of a compound enclosing the tower site , a tower structure , and one or more equipment shelters that house a variety of transmitting , receiving and switching equipment .there are three principal types of towers : guyed , self- supporting lattice , and monopole .2022 a guyed tower includes a series of cables attaching separate levels of the tower to anchor foundations in the ground .a guyed tower can reach heights of up to 2000 feet .a guyed tower site for a typical broadcast tower can consist of a tract of land of up to 20 acres .2022 a lattice tower typically tapers from the bottom up and usually has three or four legs .a lattice tower can reach heights of up to 1000 feet .depending on the height of the tower , a lattice tower site for a wireless communications tower can consist of a tract of land of 10000 square feet for a rural site or less than 2500 square feet for a metropolitan site .2022 a monopole is a tubular structure that is used primarily to address space constraints or aesthetic concerns .monopoles typically have heights ranging from 50 to 200 feet .a monopole tower site of the kind typically used in metropolitan areas for a wireless communications tower can consist of a tract of land of less than 2500 square feet. .

Question: what portion of the woburn property owned by the american tower corporation is subleased?
Answer: 64.5%