as of september 24 , 2011 , the total amount of gross unrecognized tax benefits was $ 1.4 billion , of which $ 563 million , if recognized , would affect the company 2019s effective tax rate . as of september 25 , 2010 , the total amount of gross unrecognized tax benefits was $ 943 million , of which $ 404 million , if recognized , would affect the company 2019s effective tax rate . the aggregate changes in the balance of gross unrecognized tax benefits , which excludes interest and penalties , for the three years ended september 24 , 2011 , is as follows ( in millions ) : .

Table: 2011 2010 2009 beginning balance $ 943 971 $ 506 increases related to tax positions taken during a prior year 49 61 341 decreases related to tax positions taken during a prior year -39 ( 39 ) -224 ( 224 ) -24 ( 24 ) increases related to tax positions taken during the current year 425 240 151 decreases related to settlements with taxing authorities 0 -102 ( 102 ) 0 decreases related to expiration of statute of limitations -3 ( 3 ) -3 ( 3 ) -3 ( 3 ) ending balance $ 1375 $ 943 $ 971

the company includes interest and penalties related to unrecognized tax benefits within the provision for income taxes . as of september 24 , 2011 and september 25 , 2010 , the total amount of gross interest and penalties accrued was $ 261 million and $ 247 million , respectively , which is classified as non-current liabilities in the consolidated balance sheets . in connection with tax matters , the company recognized interest expense in 2011 and 2009 of $ 14 million and $ 64 million , respectively , and in 2010 the company recognized an interest benefit of $ 43 million . the company is subject to taxation and files income tax returns in the u.s . federal jurisdiction and in many state and foreign jurisdictions . for u.s . federal income tax purposes , all years prior to 2004 are closed . the internal revenue service ( the 201cirs 201d ) has completed its field audit of the company 2019s federal income tax returns for the years 2004 through 2006 and proposed certain adjustments . the company has contested certain of these adjustments through the irs appeals office . the irs is currently examining the years 2007 through 2009 . in addition , the company is also subject to audits by state , local and foreign tax authorities . in major states and major foreign jurisdictions , the years subsequent to 1988 and 2001 , respectively , generally remain open and could be subject to examination by the taxing authorities . management believes that an adequate provision has been made for any adjustments that may result from tax examinations . however , the outcome of tax audits cannot be predicted with certainty . if any issues addressed in the company 2019s tax audits are resolved in a manner not consistent with management 2019s expectations , the company could be required to adjust its provision for income tax in the period such resolution occurs . although timing of the resolution and/or closure of audits is not certain , the company does not believe it is reasonably possible that its unrecognized tax benefits would materially change in the next 12 months . note 6 2013 shareholders 2019 equity and share-based compensation preferred stock the company has five million shares of authorized preferred stock , none of which is issued or outstanding . under the terms of the company 2019s restated articles of incorporation , the board of directors is authorized to determine or alter the rights , preferences , privileges and restrictions of the company 2019s authorized but unissued shares of preferred stock . comprehensive income comprehensive income consists of two components , net income and other comprehensive income . other comprehensive income refers to revenue , expenses , gains and losses that under gaap are recorded as an element .

Question: how many years does the irs have under examination?
Answer: 3
Calculation: subtract(2009, 2006)
Explanation: 2006 is the last closed year .