At December 31, 2012, there was $370 million of total pretax unrecognized compensation expense related to nonvested stock options, RSU and PSU awards which will be recognized over a weighted average period of 1.8 years.
For segment reporting, share-based compensation costs are unallocated expenses.14.
Pension and Other Postretirement Benefit Plans The Company has defined benefit pension plans covering eligible employees in the United States and in certain of its international subsidiaries.
In December 2011, the Compensation and Benefits Committee of the Company’s Board of Directors approved management’s proposal to change Merck’s primary U. S.  defined benefit pension plans’ benefit formulas to “cash balance” formulas beginning for service on or after January 1, 2013.
Active participants in these plans as of December 31, 2012 are accruing pension benefits prospectively using the new cash balance formulas based on age, service, pay and interest.
However, during a transition period from January 1, 2013 through December 31, 2019, participants will earn the greater of the benefit as calculated under the employee’s legacy final average pay formula or their new cash balance formula.
For all years of service after December 31, 2019, participants will earn future benefits under only the cash balance formula.
In addition, the Company provides medical benefits, principally to its eligible U. S.  retirees and their dependents, through its other postretirement benefit plans.
In December 2011, the Company approved changes to its U. S.  retiree healthcare plans, including changes for certain employees to the contribution subsidy level and eligibility criteria for subsidized retiree medical coverage and the elimination of certain retiree dental coverage.
The Company uses December 31 as the year-end measurement date for all of its pension plans and other postretirement benefit plans.
Net Periodic Benefit Cost The net periodic benefit cost for pension and other postretirement benefit plans consisted of the following components:
## Table 0 ##
The decline in net periodic benefit cost for pension and other postretirement benefit plans in 2012 as compared with 2011 and 2010 is largely attributable to the benefit plan design changes discussed above.
The changes to Merck’s primary U. S.  defined benefit pension plans and U. S.  retiree healthcare plans reduced benefit obligations at December 31, 2011 by $752 million and $150 million, respectively, with a corresponding offset to AOCI, which is being amortized as reduction to net periodic benefit cost over the employees’ future service period (approximately 11 years).
The net periodic benefit cost attributable to U. S.  pension plans included in the above table was $268 million in 2012, $406 million in 2011 and $289 million in 2010.
In connection with restructuring actions (see Note 3), termination charges were recorded in 2012, 2011 and 2010 on pension and other postretirement benefit plans related to expanded eligibility for certain employees exiting Merck.
Also, in connection with these restructuring activities, curtailments were recorded in 2012, 2011 and 2010 on pension and other postretirement benefit plans.
In addition, settlements were recorded in 2012, 2011 and 2010 on certain domestic and international pension plans
Income taxes paid in 2012, 2011 and 2010 were $2.5 billion, $2.7 billion and $1.6 billion, respectively.
Tax benefits relating to stock option exercises reflected in paid-in capital were $94 million in 2012.
These amounts were not material in 2011 or 2010.
A reconciliation of the beginning and ending amount of unrecognized tax benefits is as follows:
## Table 1 ##
(1) Amount for 2012 reflects the settlement with the CRA as discussed below.
Amount for 2011 reflects the conclusion of the IRS examination of Merck’s 2002-2005 federal income tax returns and the resolution of the interest rate swap dispute with the IRS, both as discussed below.
If the Company were to recognize the unrecognized tax benefits of $4.4 billion at December 31, 2012, the income tax provision would reflect a favorable net impact of $3.8 billion.
The Company is under examination by numerous tax authorities in various jurisdictions globally.
The Company believes that it is reasonably possible that the total amount of unrecognized tax benefits as of December 31, 2012 could decrease by up to $900 million in the next 12 months as a result of various audit closures, settlements or the expiration of the statute of limitations.
The ultimate finalization of the Company’s examinations with relevant taxing authorities can include formal administrative and legal proceedings, which could have a significant impact on the timing of the reversal of unrecognized tax benefits.
The Company believes that its reserves for uncertain tax positions are adequate to cover existing risks or exposures.
Interest and penalties associated with uncertain tax positions amounted to a (benefit) expense of $(88) million in 2012, $(95) million in 2011 and $144 million in 2010.
Liabilities for accrued interest and penalties were $1.2 billion and $1.3 billion as of December 31, 2012 and 2011, respectively.
As previously disclosed, the Canada Revenue Agency (the “CRA”) had proposed adjustments for 1999 and 2000 relating to intercompany pricing matters and, in July 2011, the CRA issued assessments for other miscellaneous audit issues for tax years 2001-2004.
In 2012, Merck and the CRA reached a settlement for these years that calls for Merck to pay additional Canadian tax of approximately $65 million.
The Company’s unrecognized tax benefits related to these matters exceeded the settlement amount and therefore the Company recorded a net $112 million tax provision benefit in 2012.
A portion of the taxes paid is expected to be creditable for U. S.  tax purposes.
The Company had previously established reserves for these matters.
The resolution of these matters did not have a material effect on the Company’s results of operations, financial position or liquidity.
In April 2011, the Internal Revenue Service (the “IRS”) concluded its examination of Merck’s 2002- 2005 federal income tax returns and as a result the Company was required to make net payments of approximately $465 million.
The Company’s unrecognized tax benefits for the years under examination exceeded the adjustments related to this examination period and therefore the Company recorded a net $700 million tax provision benefit in 2011.
This net benefit reflects the decrease of unrecognized tax benefits for the years under examination partially offset by increases to unrecognized tax benefits for years subsequent to the examination period as a result of this settlement.
The Company disagrees with the IRS treatment of one issue raised during this examination and is appealing the matter through the IRS administrative process.
In 2010, the IRS finalized its examination of Schering-Plough’s 2003-2006 tax years.
In this audit cycle, the Company reached an agreement with the IRS on an adjustment to income related to intercompany pricing matters.
This income adjustment mostly reduced NOLs and other tax credit carryforwards.
Additionally, the Company is seeking resolution of one issue raised during this examination through the IRS administrative appeals process.
The Company’s reserves for uncertain tax positions were adequate to cover all adjustments related to this examination period.
The IRS began its examination of the 2007-2009 tax years in 2010.
Table of Contents 13.
Pension and Other Postretirement Benefit Plans The Company has defined benefit pension plans covering eligible employees in the United States and in certain of its international subsidiaries.
As a result of plan design changes approved in 2011, beginning on January 1, 2013, active participants in Merck’s primary U. S.  defined benefit pension plans are accruing pension benefits using new cash balance formulas based on age, service, pay and interest.
However, during a transition period from January 1, 2013 through December 31, 2019, participants will earn the greater of the benefit as calculated under the employee’s legacy final average pay formula or their new cash balance formula.
For all years of service after December 31, 2019, participants will earn future benefits under only the cash balance formula.
In addition, the Company provides medical benefits, principally to its eligible U. S.  retirees and their dependents, through its other postretirement benefit plans.
The Company uses December 31 as the year-end measurement date for all of its pension plans and other postretirement benefit plans.
Net Periodic Benefit Cost The net periodic benefit cost for pension and other postretirement benefit plans consisted of the following components:
## Table 2 ##
The increase in net periodic benefit cost for pension and other postretirement benefit plans in 2013 as compared with 2012 is largely attributable to a change in the discount rate.
The net periodic benefit cost attributable to U. S.  pension plans included in the above table was $348 million in 2013, $268 million in 2012 and $406 million in 2011.
In connection with restructuring actions (see Note 3), termination charges were recorded in 2013, 2012 and 2011 on pension and other postretirement benefit plans related to expanded eligibility for certain employees exiting Merck.
Also, in connection with these restructuring activities, curtailments were recorded in 2013, 2012 and 2011 on pension and other postretirement benefit plans.
In addition, settlements were recorded in 2013, 2012 and 2011 on certain domestic and international pension plans.

Tables referenced above, in order (Table 0 first):
<table><tr><td></td><td colspan="3">Pension Benefits</td><td colspan="3">Other Postretirement Benefits</td></tr><tr><td><i>Years Ended December 31</i></td><td>2012</td><td>2011</td><td>2010</td><td>2012</td><td>2011</td><td>2010</td></tr><tr><td>Service cost</td><td>$555</td><td>$619</td><td>$584</td><td>$82</td><td>$110</td><td>$108</td></tr><tr><td>Interest cost</td><td>661</td><td>718</td><td>688</td><td>121</td><td>141</td><td>148</td></tr><tr><td>Expected return on plan assets</td><td>-970</td><td>-972</td><td>-891</td><td>-136</td><td>-142</td><td>-132</td></tr><tr><td>Net amortization</td><td>185</td><td>201</td><td>148</td><td>-35</td><td>-17</td><td>8</td></tr><tr><td>Termination benefits</td><td>27</td><td>59</td><td>54</td><td>18</td><td>29</td><td>42</td></tr><tr><td>Curtailments</td><td>-10</td><td>-86</td><td>-50</td><td>-7</td><td>1</td><td>-10</td></tr><tr><td>Settlements</td><td>18</td><td>4</td><td>-1</td><td>—</td><td>—</td><td>—</td></tr><tr><td>Net periodic benefit cost</td><td>$466</td><td>$543</td><td>$532</td><td>$43</td><td>$122</td><td>$164</td></tr></table>
<table><tr><td></td><td>2012</td><td>2011</td><td>2010</td></tr><tr><td>Balance January 1</td><td>$4,277</td><td>$4,919</td><td>$4,743</td></tr><tr><td>Additions related to current year positions</td><td>496</td><td>695</td><td>479</td></tr><tr><td>Additions related to prior year positions</td><td>58</td><td>145</td><td>124</td></tr><tr><td>Reductions for tax positions of prior years<i><sup>-1</sup></i></td><td>-320</td><td>-1,223</td><td>-157</td></tr><tr><td>Settlements</td><td>-67</td><td>-259</td><td>-256</td></tr><tr><td>Lapse of statute of limitations</td><td>-19</td><td>—</td><td>-14</td></tr><tr><td>Balance December 31</td><td>$4,425</td><td>$4,277</td><td>$4,919</td></tr></table>
<table><tr><td></td><td colspan="3">Pension Benefits</td><td colspan="3">Other Postretirement Benefits</td></tr><tr><td>Years Ended December 31</td><td>2013</td><td>2012</td><td>2011</td><td>2013</td><td>2012</td><td>2011</td></tr><tr><td>Service cost</td><td>$682</td><td>$555</td><td>$619</td><td>$102</td><td>$82</td><td>$110</td></tr><tr><td>Interest cost</td><td>665</td><td>661</td><td>718</td><td>107</td><td>121</td><td>141</td></tr><tr><td>Expected return on plan assets</td><td>-1,097</td><td>-970</td><td>-972</td><td>-126</td><td>-136</td><td>-142</td></tr><tr><td>Net amortization</td><td>336</td><td>185</td><td>201</td><td>-50</td><td>-35</td><td>-17</td></tr><tr><td>Termination benefits</td><td>58</td><td>27</td><td>59</td><td>50</td><td>18</td><td>29</td></tr><tr><td>Curtailments</td><td>-23</td><td>-10</td><td>-86</td><td>-11</td><td>-7</td><td>1</td></tr><tr><td>Settlements</td><td>23</td><td>18</td><td>4</td><td>—</td><td>—</td><td>—</td></tr><tr><td>Net periodic benefit cost</td><td>$644</td><td>$466</td><td>$543</td><td>$72</td><td>$43</td><td>$122</td></tr></table>

Question: Which year is Interest cost for Pension Benefits the highest?
Answer: 2011