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Net Defined Benefit Liabilities (Tables) | 12 Months Ended
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Dec. 31, 2018
Statement [LineItems] |
Summary of Amount Recognized in the Statements of Financial Position | The amounts recognized in the statements of financial position are determined as follows:
(In millions of Korean won) |  | December 31, 2017 |  |  | December 31, 2018 |
Present value of defined benefit obligations |  | ￦ | 1,911,166 |  |  | ￦ | 2,201,876 |
Fair value of plan assets |  |  | (1,519,779 | ) |  |  | (1,643,046 | )
Liabilities |  | ￦ | 395,079 |  |  | ￦ | 561,269 |
Assets in the statement of financial position |  | ￦ | 3,692 |  |  | ￦ | 2,439 |
Summary of Changes in the Defined Benefit Obligations | Changes in the defined benefit obligations for the years ended December 31, 2017 and 2018, are as follows:
(In millions of Korean won) |  | 2017 |  |  | 2018 |
Beginning |  | ￦ | 1,713,184 |  |  | ￦ | 1,911,166 |
Current service cost |  |  | 210,336 |  |  |  | 225,667 |
Interest expense |  |  | 38,994 |  |  |  | 51,691 |
Benefit paid |  |  | (154,600 | ) |  |  | (121,372 | )
Changes due to settlements of plan |  |  | (61 | ) |  |  | 9,801 |
Remeasurements: |  |  |  |  |  |  |  |
Actuarial gains and losses arising from changes in demographic assumptions |  |  | 3,353 |  |  |  | 4,600 |
Actuarial gains and losses arising from changes in financial assumptions |  |  | 36,946 |  |  |  | 116,458 |
Actuarial gains and losses arising from experience adjustments |  |  | 63,583 |  |  |  | (19,919 | )
Changes in scope of Consolidation |  |  | (569 | ) |  |  | 23,784 |
Ending |  | ￦ | 1,911,166 |  |  | ￦ | 2,201,876 |
Changes in the fair value of plan assets for the years ended December 31, 2017 and 2018, are as follows:
(In millions of Korean won) |  | 2017 |  |  | 2018 |
Beginning |  | ￦ | 1,334,780 |  |  | ￦ | 1,519,779 |
Interest income |  |  | 30,303 |  |  |  | 41,233 |
Remeasurements: |  |  |  |  |  |  |  |
Return on plan assets (excluding amounts included in interest income) |  |  | (5,557 | ) |  |  | 1,409 |
Benefits paid |  |  | (130,510 | ) |  |  | (116,303 | )
Employer contributions |  |  | 290,895 |  |  |  | 179,100 |
Changes in scope of consolidation |  |  | (132 | ) |  |  | 17,828 |
Ending |  | ￦ | 1,519,779 |  |  | ￦ | 1,643,046 |
Summary of Amounts Recognized in the Statement of Profit or Loss | Amounts recognized in the statement of profit or loss for the years ended December 31, 2016, 2017 and 2018, are as follows:
(In millions of Korean won) |  | 2016 |  |  | 2017 |  |  | 2018 |
Current service cost |  | ￦ | 205,114 |  |  | ￦ | 210,336 |  |  | ￦ | 225,667 |
Net Interest cost |  |  | 12,141 |  |  |  | 8,691 |  |  |  | 10,458 |
Past service cost |  |  | 424 |  |  |  | (61 | ) |  |  | 9,801 |
Transfer out |  |  | (8,737 | ) |  |  | (9,196 | ) |  |  | (13,881 | )
Total expenses |  | ￦ | 208,942 |  |  | ￦ | 209,770 |  |  | ￦ | 232,045 |
Summary of Principal Actuarial Assumptions | Principal actuarial assumptions used are as follows:
|  | December 31, 2016 |  | December 31, 2017 |  | December 31, 2018
Discount rate |  | 2.43% |  | 2.76% |  | 2.77%
Future salary increase |  | 4.10% |  | 4.51% |  | 4.61%
Summary of Expected Maturity Analysis of Undiscounted Pension Benefits | The expected maturity analysis of undiscounted pension benefits as at December 31, 2018, is as follows:
(In millions of Korean won) |  | Less than 1 year |  |  | Between 1-2 years |  |  | Between 2-5 years |  |  | Over 5 years |  |  | Total |
Pension benefits |  | ￦ | 183,106 |  |  | ￦ | 225,706 |  |  | ￦ | 726,283 |  |  | ￦ | 3,972,768 |  |  | ￦ | 5,107,863 |
Defined benefit obligations [member] |
Statement [LineItems] |
Summary of Sensitivity of the Defined Benefit Obligations | The sensitivity of the defined benefit obligations as at December 31, 2018, to changes in the principal assumptions is:
(In percentage, in millions of Korean won) |  | Effect on defined benefit obligation |
|  | Changes in assumption |  | Increase in assumption |  |  | Decrease in assumption |
Discount rate |  | 0.5% point |  | ￦ | (72,851 | ) |  | ￦ | 82,527 |
Salary growth rate |  | 0.5% point |  |  | 75,647 |  |  |  | (63,267 | )

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