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Retirement Benefits (Tables) | 12 Months Ended
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Dec. 31, 2020
Defined Benefit Plan Disclosure [Line Items] |
Schedule Of SERP Trust Assets, ABO And Contributions | Presented in the following table are the fair values of trust assets, ABO, and contributions for CMS Energy’s and Consumers’ DB SERP:
In Millions
Years Ended December 31 | 2020 | 2019
CMS Energy, including Consumers |  |  |  |
Trust assets |  | $ | 146 |  |  | $ | 143 |
ABO |  | 159 |  |  | 149 |
Contributions |  | 8 |  |  | — |
Consumers |  |  |  |
Trust assets |  | $ | 107 |  |  | $ | 104 |
ABO |  | 115 |  |  | 107 |
Contributions |  | 5 |  |  | — |
Schedule Of Assumptions Used | Presented in the following table are the weighted-average assumptions used in CMS Energy’s and Consumers’ retirement benefits plans to determine benefit obligations and net periodic benefit cost:
December 31 | 2020 | 2019 | 2018
CMS Energy, including Consumers |  |  |
Weighted average for benefit obligations 1 |  |  |
Discount rate 2 |  |  |
DB Pension Plan A | 2.73 | % | 3.37 | % | 4.48 | %
DB Pension Plan B | 2.41 |  | 3.17 |  | 4.32 |
DB SERP | 2.40 |  | 3.15 |  | 4.32 |
OPEB Plan | 2.69 |  | 3.32 |  | 4.42 |
Rate of compensation increase |  |  |
DB Pension Plan A | 3.70 |  | 3.50 |  | 3.50 |
DB SERP | 5.50 |  | 5.50 |  | 5.50 |
Weighted average for net periodic benefit cost 1 |  |  |
Service cost discount rate 2,3 |  |  |
DB Pension Plan A | 3.44 | % | 4.55 | % | 3.85 | %
DB SERP | 3.46 |  | 4.58 |  | 3.83 |
OPEB Plan | 3.57 |  | 4.63 |  | 3.93 |
Interest cost discount rate 2,3 |  |  |
DB Pension Plan A | 2.92 |  | 4.08 |  | 3.39 |
DB Pension Plan B | 2.74 |  | 3.93 |  | 3.24 |
DB SERP | 2.74 |  | 3.94 |  | 3.26 |
OPEB Plan | 2.88 |  | 4.03 |  | 3.35 |
Expected long-term rate of return on plan assets 4 |  |  |
DB Pension Plans | 6.75 |  | 7.00 |  | 7.00 |
OPEB Plan | 6.75 |  | 7.00 |  | 7.00 |
Rate of compensation increase |  |  |
DB Pension Plan A | 3.50 |  | 3.50 |  | 3.50 |
DB SERP | 5.50 |  | 5.50 |  | 5.50 |
1 The mortality assumption for benefit obligations was based on the Pri-2012 Mortality Table for 2020 and 2019 and the RP-2014 Mortality Table for 2018, with improvement scales MP-2020 for 2020, MP-2019 for 2019, and MP-2018 for 2018. The mortality assumption for net periodic benefit cost was based on the Pri-2012 Mortality Table for 2020 and the RP-2014 Mortality Table for 2019 and 2018, with improvement scales MP-2019 for 2020, MP-2018 for 2019, and MP-2017 for 2018. 2 The discount rate reflects the rate at which benefits could be effectively settled and is equal to the equivalent single rate resulting from a yield-curve analysis. This analysis incorporated the projected benefit payments specific to CMS Energy’s and Consumers’ DB Pension Plans and OPEB Plan and the yields on high-quality corporate bonds rated Aa or better. 3 CMS Energy and Consumers have elected to use a full-yield-curve approach in the estimation of service cost and interest cost; this approach applies individual spot rates along the yield curve to future projected benefit payments based on the time of payment. 4 CMS Energy and Consumers determined the long-term rate of return using historical market returns, the present and expected future economic environment, the capital market principles of risk and return, and the expert opinions of individuals and firms with financial market knowledge. CMS Energy and Consumers considered the asset allocation of the portfolio in forecasting the future expected total return of the portfolio. The goal was to determine a long-term rate of return that could be incorporated into the planning of future cash flow requirements in conjunction with the change in the liability. Annually, CMS Energy and Consumers review for reasonableness and appropriateness the forecasted returns for various classes of assets used to construct an expected return model. CMS Energy’s and Consumers’ expected long-term rate of return on the assets of the DB Pension Plans was 6.75 percent in 2020. The actual return (loss) on the assets of the DB Pension Plans was 13.6 percent in 2020, 21.0 percent in 2019, and (6.7) percent in 2018.
Schedule Of Net Benefit Costs | Presented in the following table are the costs (credits) and other changes in plan assets and benefit obligations incurred in CMS Energy’s and Consumers’ retirement benefits plans:
In Millions
| DB Pension Plans and DB SERP |  | OPEB Plan
Years Ended December 31 | 2020 | 2019 | 2018 |  | 2020 | 2019 | 2018
CMS Energy, including Consumers |  |  |  |  |  |  |  |  |  |  |  |  |
Net periodic cost (credit) |  |  |  |  |  |  |  |  |  |  |  |  |
Service cost |  | $ | 50 |  |  | $ | 41 |  |  | $ | 48 |  |  |  | $ | 16 |  |  | $ | 14 |  |  | $ | 17 |
Interest cost |  | 83 |  |  | 103 |  |  | 95 |  |  |  | 33 |  |  | 41 |  |  | 34 |
Settlement loss |  | 1 |  |  | — |  |  | — |  |  |  | — |  |  | — |  |  | — |
Expected return on plan assets |  | (191) |  |  | (162) |  |  | (149) |  |  |  | (100) |  |  | (88) |  |  | (97) |
Amortization of: |  |  |  |  |  |  |  |  |  |  |  |  |
Net loss |  | 95 |  |  | 50 |  |  | 76 |  |  |  | 15 |  |  | 26 |  |  | 15 |
Prior service cost (credit) |  | 1 |  |  | 1 |  |  | 3 |  |  |  | (56) |  |  | (62) |  |  | (67) |
Settlement loss |  | 2 |  |  | — |  |  | — |  |  |  | — |  |  | — |  |  | — |
Net periodic cost (credit) |  | $ | 41 |  |  | $ | 33 |  |  | $ | 73 |  |  |  | $ | (92) |  |  | $ | (69) |  |  | $ | (98) |
Consumers |  |  |  |  |  |  |  |  |  |  |  |  |
Net periodic cost (credit) |  |  |  |  |  |  |  |  |  |  |  |  |
Service cost |  | $ | 49 |  |  | $ | 40 |  |  | $ | 47 |  |  |  | $ | 15 |  |  | $ | 13 |  |  | $ | 16 |
Interest cost |  | 78 |  |  | 97 |  |  | 88 |  |  |  | 31 |  |  | 40 |  |  | 33 |
Expected return on plan assets |  | (181) |  |  | (153) |  |  | (139) |  |  |  | (93) |  |  | (82) |  |  | (91) |
Amortization of: |  |  |  |  |  |  |  |  |  |  |  |  |
Net loss |  | 90 |  |  | 47 |  |  | 73 |  |  |  | 15 |  |  | 26 |  |  | 16 |
Prior service cost (credit) |  | 1 |  |  | 1 |  |  | 3 |  |  |  | (54) |  |  | (61) |  |  | (65) |
Settlement loss |  | 2 |  |  | — |  |  | — |  |  |  | — |  |  | — |  |  | — |
Net periodic cost (credit) |  | $ | 39 |  |  | $ | 32 |  |  | $ | 72 |  |  |  | $ | (86) |  |  | $ | (64) |  |  | $ | (91) |
Schedule Of Funded Status Of Retirement Benefit Plans | Presented in the following table are reconciliations of the funded status of CMS Energy’s and Consumers’ retirement benefits plans with their retirement benefits plans’ liabilities:
In Millions
| DB Pension Plans |  | DB SERP |  | OPEB Plan
Years Ended December 31 | 2020 | 2019 |  | 2020 | 2019 |  | 2020 | 2019 |
CMS Energy, including Consumers |  |  |  |  |  |  |  |  |  |  |
Benefit obligation at beginning of period |  | $ | 2,973 |  |  | $ | 2,512 |  |  |  | $ | 150 |  |  | $ | 140 |  |  |  | $ | 1,165 |  |  | $ | 1,045 |  |
Service cost |  | 50 |  |  | 41 |  |  |  | — |  |  | — |  |  |  | 16 |  |  | 14 |  |
Interest cost |  | 79 |  |  | 98 |  |  |  | 4 |  |  | 5 |  |  |  | 33 |  |  | 41 |  |
Plan amendments |  | 24 |  |  | — |  |  |  | — |  |  | — |  |  |  | — |  |  | — |  |
Actuarial loss |  | 355 |  | 1 | 476 |  | 1 |  | 16 |  |  | 15 |  |  |  | 39 |  | 1 | 110 |  | 1
Benefits paid |  | (215) |  |  | (154) |  |  |  | (10) |  |  | (10) |  |  |  | (48) |  |  | (45) |  |
Benefit obligation at end of period |  | $ | 3,266 |  |  | $ | 2,973 |  |  |  | $ | 160 |  |  | $ | 150 |  |  |  | $ | 1,205 |  |  | $ | 1,165 |  |
Plan assets at fair value at beginning of period |  | $ | 2,546 |  |  | $ | 2,247 |  |  |  | $ | — |  |  | $ | — |  |  |  | $ | 1,509 |  |  | $ | 1,280 |  |
Actual return on plan assets |  | 371 |  |  | 453 |  |  |  | — |  |  | — |  |  |  | 182 |  |  | 273 |  |
Company contribution |  | 700 |  |  | — |  |  |  | 10 |  |  | 10 |  |  |  | 1 |  |  | — |  |
Actual benefits paid |  | (215) |  |  | (154) |  |  |  | (10) |  |  | (10) |  |  |  | (47) |  |  | (44) |  |
Plan assets at fair value at end of period |  | $ | 3,402 |  |  | $ | 2,546 |  |  |  | $ | — |  |  | $ | — |  |  |  | $ | 1,645 |  |  | $ | 1,509 |  |
Funded status |  | $ | 136 |  | 2 | $ | (427) |  | 2 |  | $ | (160) |  |  | $ | (150) |  |  |  | $ | 440 |  |  | $ | 344 |  |
Consumers |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Benefit obligation at beginning of period |  |  |  |  |  |  | $ | 109 |  |  | $ | 101 |  |  |  | $ | 1,120 |  |  | $ | 1,004 |  |
Service cost |  |  |  |  |  |  | — |  |  | — |  |  |  | 15 |  |  | 13 |  |
Interest cost |  |  |  |  |  |  | 3 |  |  | 4 |  |  |  | 31 |  |  | 40 |  |
Actuarial loss |  |  |  |  |  |  | 12 |  |  | 11 |  |  |  | 37 |  | 1 | 106 |  | 1
Benefits paid |  |  |  |  |  |  | (7) |  |  | (7) |  |  |  | (45) |  |  | (43) |  |
Benefit obligation at end of period |  |  |  |  |  |  | $ | 117 |  |  | $ | 109 |  |  |  | $ | 1,158 |  |  | $ | 1,120 |  |
Plan assets at fair value at beginning of period |  |  |  |  |  |  | $ | — |  |  | $ | — |  |  |  | $ | 1,410 |  |  | $ | 1,197 |  |
Actual return on plan assets |  |  |  |  |  |  | — |  |  | — |  |  |  | 169 |  |  | 255 |  |
Company contribution |  |  |  |  |  |  | 7 |  |  | 7 |  |  |  | 1 |  |  | — |  |
Actual benefits paid |  |  |  |  |  |  | (7) |  |  | (7) |  |  |  | (45) |  |  | (42) |  |
Plan assets at fair value at end of period |  |  |  |  |  |  | $ | — |  |  | $ | — |  |  |  | $ | 1,535 |  |  | $ | 1,410 |  |
Funded status |  |  |  |  |  |  | $ | (117) |  |  | $ | (109) |  |  |  | $ | 377 |  |  | $ | 290 |  |
1 The actuarial loss for 2020 and 2019 for the DB Pension Plans was primarily the result of lower discount rates and lower interest rates used to calculate the value of lump-sum payments. The actuarial loss for 2020 and 2019 for the OPEB Plan was primarily the result of lower discount rates. 2 The total funded status of the DB Pension Plans attributable to Consumers, based on an allocation of expenses, was $138 million at December 31, 2020 and $(408) million at December 31, 2019.
Schedule Of Retirement Benefit Plan Assets (Liabilities) | Presented in the following table is the classification of CMS Energy’s and Consumers’ retirement benefit plans’ assets and liabilities:
In Millions
December 31 | 2020 | 2019
CMS Energy, including Consumers |  |  |  |
Non-current assets |  |  |  |
DB Pension Plans |  | $ | 136 |  |  | $ | 104 |
OPEB Plan |  | 440 |  |  | 344 |
Current liabilities |  |  |  |
DB SERP |  | 10 |  |  | 10 |
Non-current liabilities |  |  |  |
DB Pension Plans |  | — |  |  | 531 |
DB SERP |  | 150 |  |  | 140 |
Consumers |  |  |  |
Non-current assets |  |  |  |
DB Pension Plans |  | $ | 138 |  |  | $ | 109 |
OPEB Plan |  | 377 |  |  | 290 |
Current liabilities |  |  |  |
DB SERP |  | 7 |  |  | 7 |
Non-current liabilities |  |  |  |
DB Pension Plans |  | — |  |  | 517 |
DB SERP |  | 110 |  |  | 102 |
Schedule Of Accumulated And Projected Benefit Obligations | At December 31, 2019, the PBO and ABO for one of the defined benefit pension plans exceeded plan assets; presented in the following table is information related to that plan:
In Millions
December 31 | 2019
CMS Energy, including Consumers |  |
PBO |  | $ | 1,736 |
ABO |  | 1,398 |
Fair value of plan assets |  | 1,205 |
Schedule Of Net Periodic Benefit Cost Not Yet Recognized | For additional details on regulatory assets, see Note 3, Regulatory Matters.
In Millions
| DB Pension Plans and DB SERP |  | OPEB Plan
December 31 | 2020 | 2019 |  | 2020 | 2019
CMS Energy, including Consumers |  |  |  |  |  |  |  |  |
Regulatory assets |  |  |  |  |  |  |  |  |
Net loss |  | $ | 1,194 |  |  | $ | 1,114 |  |  |  | $ | 254 |  |  | $ | 308 |
Prior service cost (credit) |  | 29 |  |  | 8 |  |  |  | (246) |  |  | (300) |
Regulatory assets |  | $ | 1,223 |  |  | $ | 1,122 |  |  |  | $ | 8 |  |  | $ | 8 |
AOCI |  |  |  |  |  |  |  |  |
Net loss (gain) |  | 120 |  |  | 105 |  |  |  | (10) |  |  | (6) |
Prior service cost (credit) |  | 1 |  |  | — |  |  |  | (6) |  |  | (8) |
Total amounts recognized in regulatory assets and AOCI |  | $ | 1,344 |  |  | $ | 1,227 |  |  |  | $ | (8) |  |  | $ | (6) |
Consumers |  |  |  |  |  |  |  |  |
Regulatory assets |  |  |  |  |  |  |  |  |
Net loss |  | $ | 1,194 |  |  | $ | 1,114 |  |  |  | $ | 254 |  |  | $ | 308 |
Prior service cost (credit) |  | 29 |  |  | 8 |  |  |  | (246) |  |  | (300) |
Regulatory assets |  | $ | 1,223 |  |  | $ | 1,122 |  |  |  | $ | 8 |  |  | $ | 8 |
AOCI |  |  |  |  |  |  |  |  |
Net loss |  | 47 |  |  | 36 |  |  |  | — |  |  | — |
Total amounts recognized in regulatory assets and AOCI |  | $ | 1,270 |  |  | $ | 1,158 |  |  |  | $ | 8 |  |  | $ | 8 |
Schedule Of Allocation Of Plan Assets | For additional details regarding the fair value hierarchy, see Note 6, Fair Value Measurements.
In Millions
| DB Pension Plans
| December 31, 2020 |  | December 31, 2019
| Total | Level 1 | Level 2 |  | Total | Level 1 | Level 2
CMS Energy, including Consumers
Cash and short-term investments |  | $ | 115 |  |  | $ | 115 |  |  | $ | — |  |  |  | $ | 44 |  |  | $ | 44 |  |  | $ | — |
U.S. government and agencies securities |  | 150 |  |  | — |  |  | 150 |  |  |  | 66 |  |  | — |  |  | 66 |
Corporate debt |  | 540 |  |  | — |  |  | 540 |  |  |  | 493 |  |  | — |  |  | 493 |
State and municipal bonds |  | 11 |  |  | — |  |  | 11 |  |  |  | 17 |  |  | — |  |  | 17 |
Foreign corporate bonds |  | 41 |  |  | — |  |  | 41 |  |  |  | 33 |  |  | — |  |  | 33 |
Mutual funds |  | 971 |  |  | 971 |  |  | — |  |  |  | 640 |  |  | 640 |  |  | — |
|  | $ | 1,828 |  |  | $ | 1,086 |  |  | $ | 742 |  |  |  | $ | 1,293 |  |  | $ | 684 |  |  | $ | 609 |
Pooled funds |  | 1,574 |  |  |  |  |  |  |  | 1,253 |  |  |  |  |
Total |  | $ | 3,402 |  |  |  |  |  |  |  | $ | 2,546 |  |  |  |  |
In Millions
| OPEB Plan
| December 31, 2020 |  | December 31, 2019
| Total | Level 1 | Level 2 |  | Total | Level 1 | Level 2
CMS Energy, including Consumers
Cash and short-term investments |  | $ | 33 |  |  | $ | 33 |  |  | $ | — |  |  |  | $ | 9 |  |  | $ | 9 |  |  | $ | — |
U.S. government and agencies securities |  | 18 |  |  | — |  |  | 18 |  |  |  | 10 |  |  | — |  |  | 10 |
Corporate debt |  | 64 |  |  | — |  |  | 64 |  |  |  | 71 |  |  | — |  |  | 71 |
State and municipal bonds |  | 2 |  |  | — |  |  | 2 |  |  |  | 2 |  |  | — |  |  | 2 |
Foreign corporate bonds |  | 5 |  |  | — |  |  | 5 |  |  |  | 5 |  |  | — |  |  | 5 |
Common stocks |  | 66 |  |  | 66 |  |  | — |  |  |  | 55 |  |  | 55 |  |  | — |
Mutual funds |  | 807 |  |  | 807 |  |  | — |  |  |  | 713 |  |  | 713 |  |  | — |
|  | $ | 995 |  |  | $ | 906 |  |  | $ | 89 |  |  |  | $ | 865 |  |  | $ | 777 |  |  | $ | 88 |
Pooled funds |  | 650 |  |  |  |  |  |  |  | 644 |  |  |  |  |
Total |  | $ | 1,645 |  |  |  |  |  |  |  | $ | 1,509 |  |  |  |  |
Schedule Of Asset Allocation | Asset Allocations: Presented in the following table are the investment components of the assets of CMS Energy’s DB Pension Plans and OPEB Plan as of December 31, 2020:
| DB Pension Plans | OPEB Plan
Equity securities |  | 55.0 | % |  | 50.0 | %
Fixed-income securities |  | 34.0 |  |  | 30.0 |
Multi-asset investments |  | 11.0 |  |  | 20.0 |
|  | 100.0 | % |  | 100.0 | %
Schedule Of Plan Contributions | Presented in the following table are the contributions to CMS Energy’s and Consumers’ DB Pension Plans and OPEB Plan:
In Millions
Years Ended December 31 | 2020 | 2019
CMS Energy, including Consumers |  |  |  |
DB Pension Plans |  | $ | 700 |  |  | $ | — |
OPEB Plan |  | 1 |  |  | — |
Consumers |  |  |  |
DB Pension Plans |  | $ | 682 |  |  | $ | — |
OPEB Plan |  | 1 |  |  | — |
Schedule Of Expected Benefit Payments | Presented in the following table are the expected benefit payments for each of the next five years and the five-year period thereafter:
In Millions
| DB Pension Plans | DB SERP | OPEB Plan
CMS Energy, including Consumers |  |  |  |  |  |
2021 |  | $ | 191 |  |  | $ | 10 |  |  | $ | 52 |
2022 |  | 188 |  |  | 10 |  |  | 54 |
2023 |  | 184 |  |  | 10 |  |  | 56 |
2024 |  | 182 |  |  | 10 |  |  | 57 |
2025 |  | 182 |  |  | 10 |  |  | 58 |
2026-2030 |  | 890 |  |  | 46 |  |  | 299 |
Consumers |  |  |  |  |  |
2021 |  | $ | 181 |  |  | $ | 7 |  |  | $ | 50 |
2022 |  | 178 |  |  | 7 |  |  | 52 |
2023 |  | 175 |  |  | 7 |  |  | 53 |
2024 |  | 173 |  |  | 7 |  |  | 55 |
2025 |  | 172 |  |  | 7 |  |  | 56 |
2026-2030 |  | 845 |  |  | 32 |  |  | 286 |
Consumers Energy Company |
Defined Benefit Plan Disclosure [Line Items] |
Schedule Of SERP Trust Assets, ABO And Contributions | Presented in the following table are the fair values of trust assets, ABO, and contributions for CMS Energy’s and Consumers’ DB SERP:
In Millions
Years Ended December 31 | 2020 | 2019
CMS Energy, including Consumers |  |  |  |
Trust assets |  | $ | 146 |  |  | $ | 143 |
ABO |  | 159 |  |  | 149 |
Contributions |  | 8 |  |  | — |
Consumers |  |  |  |
Trust assets |  | $ | 107 |  |  | $ | 104 |
ABO |  | 115 |  |  | 107 |
Contributions |  | 5 |  |  | — |
Schedule Of Assumptions Used | Presented in the following table are the weighted-average assumptions used in CMS Energy’s and Consumers’ retirement benefits plans to determine benefit obligations and net periodic benefit cost:
December 31 | 2020 | 2019 | 2018
CMS Energy, including Consumers |  |  |
Weighted average for benefit obligations 1 |  |  |
Discount rate 2 |  |  |
DB Pension Plan A | 2.73 | % | 3.37 | % | 4.48 | %
DB Pension Plan B | 2.41 |  | 3.17 |  | 4.32 |
DB SERP | 2.40 |  | 3.15 |  | 4.32 |
OPEB Plan | 2.69 |  | 3.32 |  | 4.42 |
Rate of compensation increase |  |  |
DB Pension Plan A | 3.70 |  | 3.50 |  | 3.50 |
DB SERP | 5.50 |  | 5.50 |  | 5.50 |
Weighted average for net periodic benefit cost 1 |  |  |
Service cost discount rate 2,3 |  |  |
DB Pension Plan A | 3.44 | % | 4.55 | % | 3.85 | %
DB SERP | 3.46 |  | 4.58 |  | 3.83 |
OPEB Plan | 3.57 |  | 4.63 |  | 3.93 |
Interest cost discount rate 2,3 |  |  |
DB Pension Plan A | 2.92 |  | 4.08 |  | 3.39 |
DB Pension Plan B | 2.74 |  | 3.93 |  | 3.24 |
DB SERP | 2.74 |  | 3.94 |  | 3.26 |
OPEB Plan | 2.88 |  | 4.03 |  | 3.35 |
Expected long-term rate of return on plan assets 4 |  |  |
DB Pension Plans | 6.75 |  | 7.00 |  | 7.00 |
OPEB Plan | 6.75 |  | 7.00 |  | 7.00 |
Rate of compensation increase |  |  |
DB Pension Plan A | 3.50 |  | 3.50 |  | 3.50 |
DB SERP | 5.50 |  | 5.50 |  | 5.50 |
1 The mortality assumption for benefit obligations was based on the Pri-2012 Mortality Table for 2020 and 2019 and the RP-2014 Mortality Table for 2018, with improvement scales MP-2020 for 2020, MP-2019 for 2019, and MP-2018 for 2018. The mortality assumption for net periodic benefit cost was based on the Pri-2012 Mortality Table for 2020 and the RP-2014 Mortality Table for 2019 and 2018, with improvement scales MP-2019 for 2020, MP-2018 for 2019, and MP-2017 for 2018. 2 The discount rate reflects the rate at which benefits could be effectively settled and is equal to the equivalent single rate resulting from a yield-curve analysis. This analysis incorporated the projected benefit payments specific to CMS Energy’s and Consumers’ DB Pension Plans and OPEB Plan and the yields on high-quality corporate bonds rated Aa or better. 3 CMS Energy and Consumers have elected to use a full-yield-curve approach in the estimation of service cost and interest cost; this approach applies individual spot rates along the yield curve to future projected benefit payments based on the time of payment. 4 CMS Energy and Consumers determined the long-term rate of return using historical market returns, the present and expected future economic environment, the capital market principles of risk and return, and the expert opinions of individuals and firms with financial market knowledge. CMS Energy and Consumers considered the asset allocation of the portfolio in forecasting the future expected total return of the portfolio. The goal was to determine a long-term rate of return that could be incorporated into the planning of future cash flow requirements in conjunction with the change in the liability. Annually, CMS Energy and Consumers review for reasonableness and appropriateness the forecasted returns for various classes of assets used to construct an expected return model. CMS Energy’s and Consumers’ expected long-term rate of return on the assets of the DB Pension Plans was 6.75 percent in 2020. The actual return (loss) on the assets of the DB Pension Plans was 13.6 percent in 2020, 21.0 percent in 2019, and (6.7) percent in 2018.
Schedule Of Net Benefit Costs | Presented in the following table are the costs (credits) and other changes in plan assets and benefit obligations incurred in CMS Energy’s and Consumers’ retirement benefits plans:
In Millions
| DB Pension Plans and DB SERP |  | OPEB Plan
Years Ended December 31 | 2020 | 2019 | 2018 |  | 2020 | 2019 | 2018
CMS Energy, including Consumers |  |  |  |  |  |  |  |  |  |  |  |  |
Net periodic cost (credit) |  |  |  |  |  |  |  |  |  |  |  |  |
Service cost |  | $ | 50 |  |  | $ | 41 |  |  | $ | 48 |  |  |  | $ | 16 |  |  | $ | 14 |  |  | $ | 17 |
Interest cost |  | 83 |  |  | 103 |  |  | 95 |  |  |  | 33 |  |  | 41 |  |  | 34 |
Settlement loss |  | 1 |  |  | — |  |  | — |  |  |  | — |  |  | — |  |  | — |
Expected return on plan assets |  | (191) |  |  | (162) |  |  | (149) |  |  |  | (100) |  |  | (88) |  |  | (97) |
Amortization of: |  |  |  |  |  |  |  |  |  |  |  |  |
Net loss |  | 95 |  |  | 50 |  |  | 76 |  |  |  | 15 |  |  | 26 |  |  | 15 |
Prior service cost (credit) |  | 1 |  |  | 1 |  |  | 3 |  |  |  | (56) |  |  | (62) |  |  | (67) |
Settlement loss |  | 2 |  |  | — |  |  | — |  |  |  | — |  |  | — |  |  | — |
Net periodic cost (credit) |  | $ | 41 |  |  | $ | 33 |  |  | $ | 73 |  |  |  | $ | (92) |  |  | $ | (69) |  |  | $ | (98) |
Consumers |  |  |  |  |  |  |  |  |  |  |  |  |
Net periodic cost (credit) |  |  |  |  |  |  |  |  |  |  |  |  |
Service cost |  | $ | 49 |  |  | $ | 40 |  |  | $ | 47 |  |  |  | $ | 15 |  |  | $ | 13 |  |  | $ | 16 |
Interest cost |  | 78 |  |  | 97 |  |  | 88 |  |  |  | 31 |  |  | 40 |  |  | 33 |
Expected return on plan assets |  | (181) |  |  | (153) |  |  | (139) |  |  |  | (93) |  |  | (82) |  |  | (91) |
Amortization of: |  |  |  |  |  |  |  |  |  |  |  |  |
Net loss |  | 90 |  |  | 47 |  |  | 73 |  |  |  | 15 |  |  | 26 |  |  | 16 |
Prior service cost (credit) |  | 1 |  |  | 1 |  |  | 3 |  |  |  | (54) |  |  | (61) |  |  | (65) |
Settlement loss |  | 2 |  |  | — |  |  | — |  |  |  | — |  |  | — |  |  | — |
Net periodic cost (credit) |  | $ | 39 |  |  | $ | 32 |  |  | $ | 72 |  |  |  | $ | (86) |  |  | $ | (64) |  |  | $ | (91) |
Schedule Of Funded Status Of Retirement Benefit Plans | Presented in the following table are reconciliations of the funded status of CMS Energy’s and Consumers’ retirement benefits plans with their retirement benefits plans’ liabilities:
In Millions
| DB Pension Plans |  | DB SERP |  | OPEB Plan
Years Ended December 31 | 2020 | 2019 |  | 2020 | 2019 |  | 2020 | 2019 |
CMS Energy, including Consumers |  |  |  |  |  |  |  |  |  |  |
Benefit obligation at beginning of period |  | $ | 2,973 |  |  | $ | 2,512 |  |  |  | $ | 150 |  |  | $ | 140 |  |  |  | $ | 1,165 |  |  | $ | 1,045 |  |
Service cost |  | 50 |  |  | 41 |  |  |  | — |  |  | — |  |  |  | 16 |  |  | 14 |  |
Interest cost |  | 79 |  |  | 98 |  |  |  | 4 |  |  | 5 |  |  |  | 33 |  |  | 41 |  |
Plan amendments |  | 24 |  |  | — |  |  |  | — |  |  | — |  |  |  | — |  |  | — |  |
Actuarial loss |  | 355 |  | 1 | 476 |  | 1 |  | 16 |  |  | 15 |  |  |  | 39 |  | 1 | 110 |  | 1
Benefits paid |  | (215) |  |  | (154) |  |  |  | (10) |  |  | (10) |  |  |  | (48) |  |  | (45) |  |
Benefit obligation at end of period |  | $ | 3,266 |  |  | $ | 2,973 |  |  |  | $ | 160 |  |  | $ | 150 |  |  |  | $ | 1,205 |  |  | $ | 1,165 |  |
Plan assets at fair value at beginning of period |  | $ | 2,546 |  |  | $ | 2,247 |  |  |  | $ | — |  |  | $ | — |  |  |  | $ | 1,509 |  |  | $ | 1,280 |  |
Actual return on plan assets |  | 371 |  |  | 453 |  |  |  | — |  |  | — |  |  |  | 182 |  |  | 273 |  |
Company contribution |  | 700 |  |  | — |  |  |  | 10 |  |  | 10 |  |  |  | 1 |  |  | — |  |
Actual benefits paid |  | (215) |  |  | (154) |  |  |  | (10) |  |  | (10) |  |  |  | (47) |  |  | (44) |  |
Plan assets at fair value at end of period |  | $ | 3,402 |  |  | $ | 2,546 |  |  |  | $ | — |  |  | $ | — |  |  |  | $ | 1,645 |  |  | $ | 1,509 |  |
Funded status |  | $ | 136 |  | 2 | $ | (427) |  | 2 |  | $ | (160) |  |  | $ | (150) |  |  |  | $ | 440 |  |  | $ | 344 |  |
Consumers |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Benefit obligation at beginning of period |  |  |  |  |  |  | $ | 109 |  |  | $ | 101 |  |  |  | $ | 1,120 |  |  | $ | 1,004 |  |
Service cost |  |  |  |  |  |  | — |  |  | — |  |  |  | 15 |  |  | 13 |  |
Interest cost |  |  |  |  |  |  | 3 |  |  | 4 |  |  |  | 31 |  |  | 40 |  |
Actuarial loss |  |  |  |  |  |  | 12 |  |  | 11 |  |  |  | 37 |  | 1 | 106 |  | 1
Benefits paid |  |  |  |  |  |  | (7) |  |  | (7) |  |  |  | (45) |  |  | (43) |  |
Benefit obligation at end of period |  |  |  |  |  |  | $ | 117 |  |  | $ | 109 |  |  |  | $ | 1,158 |  |  | $ | 1,120 |  |
Plan assets at fair value at beginning of period |  |  |  |  |  |  | $ | — |  |  | $ | — |  |  |  | $ | 1,410 |  |  | $ | 1,197 |  |
Actual return on plan assets |  |  |  |  |  |  | — |  |  | — |  |  |  | 169 |  |  | 255 |  |
Company contribution |  |  |  |  |  |  | 7 |  |  | 7 |  |  |  | 1 |  |  | — |  |
Actual benefits paid |  |  |  |  |  |  | (7) |  |  | (7) |  |  |  | (45) |  |  | (42) |  |
Plan assets at fair value at end of period |  |  |  |  |  |  | $ | — |  |  | $ | — |  |  |  | $ | 1,535 |  |  | $ | 1,410 |  |
Funded status |  |  |  |  |  |  | $ | (117) |  |  | $ | (109) |  |  |  | $ | 377 |  |  | $ | 290 |  |
1 The actuarial loss for 2020 and 2019 for the DB Pension Plans was primarily the result of lower discount rates and lower interest rates used to calculate the value of lump-sum payments. The actuarial loss for 2020 and 2019 for the OPEB Plan was primarily the result of lower discount rates. 2 The total funded status of the DB Pension Plans attributable to Consumers, based on an allocation of expenses, was $138 million at December 31, 2020 and $(408) million at December 31, 2019.
Schedule Of Retirement Benefit Plan Assets (Liabilities) | Presented in the following table is the classification of CMS Energy’s and Consumers’ retirement benefit plans’ assets and liabilities:
In Millions
December 31 | 2020 | 2019
CMS Energy, including Consumers |  |  |  |
Non-current assets |  |  |  |
DB Pension Plans |  | $ | 136 |  |  | $ | 104 |
OPEB Plan |  | 440 |  |  | 344 |
Current liabilities |  |  |  |
DB SERP |  | 10 |  |  | 10 |
Non-current liabilities |  |  |  |
DB Pension Plans |  | — |  |  | 531 |
DB SERP |  | 150 |  |  | 140 |
Consumers |  |  |  |
Non-current assets |  |  |  |
DB Pension Plans |  | $ | 138 |  |  | $ | 109 |
OPEB Plan |  | 377 |  |  | 290 |
Current liabilities |  |  |  |
DB SERP |  | 7 |  |  | 7 |
Non-current liabilities |  |  |  |
DB Pension Plans |  | — |  |  | 517 |
DB SERP |  | 110 |  |  | 102 |
Schedule Of Net Periodic Benefit Cost Not Yet Recognized | For additional details on regulatory assets, see Note 3, Regulatory Matters.
In Millions
| DB Pension Plans and DB SERP |  | OPEB Plan
December 31 | 2020 | 2019 |  | 2020 | 2019
CMS Energy, including Consumers |  |  |  |  |  |  |  |  |
Regulatory assets |  |  |  |  |  |  |  |  |
Net loss |  | $ | 1,194 |  |  | $ | 1,114 |  |  |  | $ | 254 |  |  | $ | 308 |
Prior service cost (credit) |  | 29 |  |  | 8 |  |  |  | (246) |  |  | (300) |
Regulatory assets |  | $ | 1,223 |  |  | $ | 1,122 |  |  |  | $ | 8 |  |  | $ | 8 |
AOCI |  |  |  |  |  |  |  |  |
Net loss (gain) |  | 120 |  |  | 105 |  |  |  | (10) |  |  | (6) |
Prior service cost (credit) |  | 1 |  |  | — |  |  |  | (6) |  |  | (8) |
Total amounts recognized in regulatory assets and AOCI |  | $ | 1,344 |  |  | $ | 1,227 |  |  |  | $ | (8) |  |  | $ | (6) |
Consumers |  |  |  |  |  |  |  |  |
Regulatory assets |  |  |  |  |  |  |  |  |
Net loss |  | $ | 1,194 |  |  | $ | 1,114 |  |  |  | $ | 254 |  |  | $ | 308 |
Prior service cost (credit) |  | 29 |  |  | 8 |  |  |  | (246) |  |  | (300) |
Regulatory assets |  | $ | 1,223 |  |  | $ | 1,122 |  |  |  | $ | 8 |  |  | $ | 8 |
AOCI |  |  |  |  |  |  |  |  |
Net loss |  | 47 |  |  | 36 |  |  |  | — |  |  | — |
Total amounts recognized in regulatory assets and AOCI |  | $ | 1,270 |  |  | $ | 1,158 |  |  |  | $ | 8 |  |  | $ | 8 |
Schedule Of Plan Contributions | Presented in the following table are the contributions to CMS Energy’s and Consumers’ DB Pension Plans and OPEB Plan:
In Millions
Years Ended December 31 | 2020 | 2019
CMS Energy, including Consumers |  |  |  |
DB Pension Plans |  | $ | 700 |  |  | $ | — |
OPEB Plan |  | 1 |  |  | — |
Consumers |  |  |  |
DB Pension Plans |  | $ | 682 |  |  | $ | — |
OPEB Plan |  | 1 |  |  | — |
Schedule Of Expected Benefit Payments | Presented in the following table are the expected benefit payments for each of the next five years and the five-year period thereafter:
In Millions
| DB Pension Plans | DB SERP | OPEB Plan
CMS Energy, including Consumers |  |  |  |  |  |
2021 |  | $ | 191 |  |  | $ | 10 |  |  | $ | 52 |
2022 |  | 188 |  |  | 10 |  |  | 54 |
2023 |  | 184 |  |  | 10 |  |  | 56 |
2024 |  | 182 |  |  | 10 |  |  | 57 |
2025 |  | 182 |  |  | 10 |  |  | 58 |
2026-2030 |  | 890 |  |  | 46 |  |  | 299 |
Consumers |  |  |  |  |  |
2021 |  | $ | 181 |  |  | $ | 7 |  |  | $ | 50 |
2022 |  | 178 |  |  | 7 |  |  | 52 |
2023 |  | 175 |  |  | 7 |  |  | 53 |
2024 |  | 173 |  |  | 7 |  |  | 55 |
2025 |  | 172 |  |  | 7 |  |  | 56 |
2026-2030 |  | 845 |  |  | 32 |  |  | 286 |

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