pre_text: Unfunded Status The following table presents the unfunded status of the Combined Pension Plan and post-retirement benefit plans: The current portion of our post-retirement benefit obligations is recorded on our consolidated balance sheets in accrued expenses and other current liabilities-salaries and benefits.
table: Combined Pension Plan Post-Retirement Benefit Plans
table: Years Ended December 31, Years Ended December 31,
table: 2019 2018 2019 2018
table: (Dollars in millions)
table: Benefit obligation $(12,217) (11,594) (3,037) (2,977)
table: Fair value of plan assets 10,493 10,033 13 18
table: Unfunded status (1,724) (1,561) (3,024) (2,959)
table: Current portion of unfunded status — — (224) (252)
table: Non-current portion of unfunded status $(1,724) (1,561) (2,800) (2,707)
question: Analyse this data from a financial earnings document. What is the difference in the fair value of plan assets under the combined pension plan in 2019?