Use the following to answer Questions 13-15. Global Data Service ("GDS") has several defined benefit pension plans (the "Plans") covering substantially all its employees. In general, employees become fully vested upon

attaining 5 years of service, and benefits are based on years of service and earnings. GDS's funding policy is to contribute amounts that fall within the range of deductible contributions for income tax purposes. The following tables provide a reconciliation of the changes in the Plans' benefit obligations and fair value of plan assets for the years ended December 31, 2021, 2020 and 2019 (in millions): 2021 2020 Reconciliation of Benefit Obligations Obligation at January 1 Service cost Interest cost Plan amendments Actuarial loss Employee contributions Benefits paid Foreign currency changes Other Obligation at December 31 Reconciliation of Fair Value of Plan Assets Fair value of plan assets at January 1 Actual retum on plan assets Company contributions Employee contributions Benefits paid Foreign currency changes Fair value of plan assets at December 31 Unamortized net actuarial loss Unamortized past service cost Net amount reported in accumulated other comprehensive income Service cost Interest cost $3,144 84 199 7 Expected retum on plan assets Amortization of net actuarial loss Amortization of past service cost Other Net periodic pension cost in P&L. 476 6 (181) (293) Discount rate Compensation growth rate Long-term rate of retum on assets $3,442 (181) (303) $2,825 $2,634 $2,129 441 228 6 2021 $1,108 $2,708 70 180 2021 $84 199 26 165 (208) 51 18 6 (213) 207 $144 (5) 2021 6.4% 4.9% 7.9% 229 311 6 The following table includes the amounts reported in "accumulated other comprehensive income" for the years ended December 31, 2021, 2020 and 2019 (in millions): (213) 172 $2,634 $3,144 $2,708 2019 2020 2019 $939 94 111 $1,202 $1,050 The following table provides the components of periodic pension cost recognized in the profit and loss statement (P&L) for the years ended December 31, 2021, 2020 and 2019 (in millions) 2020 $70 180 (169) 69 $2,163 54 151 17 7 $174 223 1 (162) 257 (4) 2020 6.8% 4.9% 8.3% S $1,645 203 214 1 (162) 228 $2,129 $918 100 $1,018 The weighted average assumptions used in the measurement of GDS's periodic pension cost are shown in the following table for the years ended December 31, 2021, 2020 and 2019: 2019 $54 151 (132) 42 GDS prepares its financial statements in accordance with U.S. Generally Accepted Accounting Princinles 7 $133 11 2019 7.1% 4.9% 8.3%/n13. What is the most likely cause of the actuarial loss reported in the benefit obligation reconciliation for the years 2020 and 2021? a. b. The discount rate. The compensation growth rate. The difference in the expected return and the actual return on assets. 5