there are inherent limitations on the effectiveness of our controls . we do not expect that our disclosure controls or our internal control over financial reporting will prevent or detect all errors and all fraud . a control system , no matter how well-designed and operated , can provide only reasonable , not absolute , assurance that the control system 2019s objectives will be met . the design of a control system must reflect the fact that resource constraints exist , and the benefits of controls must be considered relative to their costs . further , because of the inherent limitations in all control systems , no evaluation of controls can provide absolute assurance that misstatements due to error or fraud will not occur or that all control issues and instances of fraud , if any , have been detected . the design of any system of controls is based in part on certain assumptions about the likelihood of future events , and there can be no assurance that any design will succeed in achieving its stated goals under all potential future conditions . projections of any evaluation of the effectiveness of controls to future periods are subject to risks . over time , controls may become inadequate due to changes in conditions or deterioration in the degree of compliance with policies or procedures . if our controls become inadequate , we could fail to meet our financial reporting obligations , our reputation may be adversely affected , our business and operating results could be harmed , and the market price of our stock could decline . item 1b . unresolved staff comments not applicable . item 2 . properties as of december 31 , 2016 , our major facilities consisted of : ( square feet in millions ) united states countries total owned facilities1 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 31.5 19.2 50.7 leased facilities2 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2.5 7.1 9.6 .
as of december 31 , 2016 what percentage by square feet of major facilities are owned?
1 leases and municipal grants on portions of the land used for these facilities expire on varying dates through 2109 . 2 leases expire on varying dates through 2058 and generally include renewals at our option . our principal executive offices are located in the u.s . and the majority of our wafer manufacturing activities in 2016 were also located in the u.s . one of our arizona wafer fabrication facilities is currently on hold and held in a safe state , and we are reserving the building for additional capacity and future technologies . incremental construction and equipment installation are required to ready the facility for its intended use . for more information on our wafer fabrication and our assembly and test facilities , see 201cmanufacturing and assembly and test 201d in part i , item 1 of this form 10-k . we believe that the facilities described above are suitable and adequate for our present purposes and that the productive capacity in our facilities is substantially being utilized or we have plans to utilize it . we do not identify or allocate assets by operating segment . for information on net property , plant and equipment by country , see 201cnote 4 : operating segments and geographic information 201d in part ii , item 8 of this form 10-k . item 3 . legal proceedings for a discussion of legal proceedings , see 201cnote 20 : commitments and contingencies 201d in part ii , item 8 of this form 10-k . item 4 . mine safety disclosures not applicable. .