52 2013 ppg annual report and form 10-k repatriation of undistributed earnings of non-u.s .subsidiaries as of december 31 , 2013 and december 31 , 2012 would have resulted in a u.s .tax cost of approximately $ 250 million and $ 110 million , respectively .the company files federal , state and local income tax returns in numerous domestic and foreign jurisdictions .in most tax jurisdictions , returns are subject to examination by the relevant tax authorities for a number of years after the returns have been filed .the company is no longer subject to examinations by tax authorities in any major tax jurisdiction for years before 2006 .additionally , the internal revenue service has completed its examination of the company 2019s u.s .federal income tax returns filed for years through 2010 .the examination of the company 2019s u.s .federal income tax return for 2011 is currently underway and is expected to be finalized during 2014 .a reconciliation of the total amounts of unrecognized tax benefits ( excluding interest and penalties ) as of december 31 follows: .
[['( millions )', '2013', '2012', '2011'], ['balance at january 1', '$ 82', '$ 107', '$ 111'], ['additions based on tax positions related to the current year', '12', '12', '15'], ['additions for tax positions of prior years', '9', '2', '17'], ['reductions for tax positions of prior years', '-10 ( 10 )', '-12 ( 12 )', '-19 ( 19 )'], ['pre-acquisition unrecognized tax benefits', '2014', '2', '2014'], ['reductions for expiration of the applicable statute of limitations', '-10 ( 10 )', '-6 ( 6 )', '-7 ( 7 )'], ['settlements', '2014', '-23 ( 23 )', '-8 ( 8 )'], ['foreign currency translation', '2', '2014', '-2 ( 2 )'], ['balance at december 31', '$ 85', '$ 82', '$ 107']]
the company expects that any reasonably possible change in the amount of unrecognized tax benefits in the next 12 months would not be significant .the total amount of unrecognized tax benefits that , if recognized , would affect the effective tax rate was $ 81 million as of december 31 , 2013 .the company recognizes accrued interest and penalties related to unrecognized tax benefits in income tax expense .as of december 31 , 2013 , 2012 and 2011 , the company had liabilities for estimated interest and penalties on unrecognized tax benefits of $ 9 million , $ 10 million and $ 15 million , respectively .the company recognized $ 2 million and $ 5 million of income in 2013 and 2012 , respectively , related to the reduction of estimated interest and penalties .the company recognized no income or expense for estimated interest and penalties during the year ended december 31 , 2011 .13 .pensions and other postretirement benefits defined benefit plans ppg has defined benefit pension plans that cover certain employees worldwide .the principal defined benefit pension plans are those in the u.s. , canada , the netherlands and the u.k .which , in the aggregate represent approximately 91% ( 91 % ) of the projected benefit obligation at december 31 , 2013 , of which the u.s .defined benefit pension plans represent the majority .ppg also sponsors welfare benefit plans that provide postretirement medical and life insurance benefits for certain u.s .and canadian employees and their dependents .these programs require retiree contributions based on retiree-selected coverage levels for certain retirees and their dependents and provide for sharing of future benefit cost increases between ppg and participants based on management discretion .the company has the right to modify or terminate certain of these benefit plans in the future .salaried and certain hourly employees in the u.s .hired on or after october 1 , 2004 , or rehired on or after october 1 , 2012 are not eligible for postretirement medical benefits .salaried employees in the u.s .hired , rehired or transferred to salaried status on or after january 1 , 2006 , and certain u.s .hourly employees hired in 2006 or thereafter are eligible to participate in a defined contribution retirement plan .these employees are not eligible for defined benefit pension plan benefits .plan design changes in january 2011 , the company approved an amendment to one of its u.s .defined benefit pension plans that represented about 77% ( 77 % ) of the total u.s .projected benefit obligation at december 31 , 2011 .depending upon the affected employee's combined age and years of service to ppg , this change resulted in certain employees no longer accruing benefits under this plan as of december 31 , 2011 , while the remaining employees will no longer accrue benefits under this plan as of december 31 , 2020 .the affected employees will participate in the company 2019s defined contribution retirement plan from the date their benefit under the defined benefit plan is frozen .the company remeasured the projected benefit obligation of this amended plan , which lowered 2011 pension expense by approximately $ 12 million .the company made similar changes to certain other u.s .defined benefit pension plans in 2011 .the company recognized a curtailment loss and special termination benefits associated with these plan amendments of $ 5 million in 2011 .the company plans to continue reviewing and potentially changing other ppg defined benefit plans in the future .separation and merger of commodity chemicals business on january 28 , 2013 , ppg completed the separation of its commodity chemicals business and the merger of the subsidiary holding the ppg commodity chemicals business with a subsidiary of georgia gulf , as discussed in note 22 , 201cseparation and merger transaction . 201d ppg transferred the defined benefit pension plan and other postretirement benefit liabilities for the affected employees in the u.s. , canada , and taiwan in the separation resulting in a net partial settlement loss of $ 33 million notes to the consolidated financial statements .

Question: what is the average increase in the balance of unrecognized tax benefits from 2011 to 2013?
Answer: 90.5%