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 2019s 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 2019s 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: .
[['years ended december 31', 'pension benefits 2013', 'pension benefits 2012', 'pension benefits 2011', 'pension benefits 2013', 'pension benefits 2012', '2011'], ['service cost', '$ 682', '$ 555', '$ 619', '$ 102', '$ 82', '$ 110'], ['interest cost', '665', '661', '718', '107', '121', '141'], ['expected return on plan assets', '-1097 ( 1097 )', '-970 ( 970 )', '-972 ( 972 )', '-126 ( 126 )', '-136 ( 136 )', '-142 ( 142 )'], ['net amortization', '336', '185', '201', '-50 ( 50 )', '-35 ( 35 )', '-17 ( 17 )'], ['termination benefits', '58', '27', '59', '50', '18', '29'], ['curtailments', '-23 ( 23 )', '-10 ( 10 )', '-86 ( 86 )', '-11 ( 11 )', '-7 ( 7 )', '1'], ['settlements', '23', '18', '4', '2014', '2014', '2014'], ['net periodic benefit cost', '$ 644', '$ 466', '$ 543', '$ 72', '$ 43', '$ 122']]
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 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 .table of contents .

Question: considering the years 2013 and 2012 , what is the variation observed in the expected return on plan assets , in millions?
Answer: 127
Explanation: it is the difference between each year's expected return on plan assets .