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Retirement Plans and Postretirement Benefit Plans (Tables) | 12 Months Ended
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Dec. 31, 2024
Retirement Plans and Postretirement Benefit Plans [Abstract] |
Schedule of Accumulated Benefit Obligations in Excess of Fair Value of Plan Assets | The details of the funded status of OGE Energy's Pension Plan, the Restoration of Retirement Income Plan and the postretirement benefit plans and the amounts included in the balance sheets for 2024 and 2023 are included in the following tables. These amounts have been recorded in Accrued Benefit Obligations with the offset in Accumulated Other Comprehensive Loss (except OG&E's portion, which is recorded as a regulatory asset as discussed in Note 1) in the balance sheets. The amounts in Accumulated Other Comprehensive Loss and those recorded as a regulatory asset represent a net periodic benefit cost to be recognized in the statements of income in future periods. The benefit obligation for OGE Energy's Pension Plan and the Restoration of Retirement Income Plan represents the projected benefit obligation, while the benefit obligation for the postretirement benefit plans represents the accumulated postretirement benefit obligation. The accumulated postretirement benefit obligation for OGE Energy's Pension Plan and Restoration of Retirement Income Plan differs from the projected benefit obligation in that the former includes no assumption about future compensation levels.
|  | OGE Energy |  |  | OG&E |
|  | Pension Plan |  |  | Restoration of Retirement Income Plan |  |  | Pension Plan |  |  | Restoration of Retirement Income Plan |
December 31 (In millions) |  | 2024 |  |  | 2023 |  |  | 2024 |  |  | 2023 |  |  | 2024 |  |  | 2023 |  |  | 2024 |  |  | 2023 |
Change in benefit obligation |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Beginning obligations |  | $ | 303.7 |  |  | $ | 358.5 |  |  | $ | 5.5 |  |  | $ | 5.8 |  |  | $ | 238.6 |  |  | $ | 288.5 |  |  | $ | — |  |  | $ | 0.5 |
Service cost |  |  | 5.3 |  |  |  | 5.4 |  |  |  | 1.0 |  |  |  | 1.0 |  |  |  | 5.3 |  |  |  | 4.4 |  |  |  | 0.1 |  |  |  | — |
Interest cost |  |  | 15.6 |  |  |  | 15.9 |  |  |  | 0.3 |  |  |  | 0.3 |  |  |  | 13.4 |  |  |  | 12.6 |  |  |  | 0.1 |  |  |  | — |
Plan settlements |  |  | — |  |  |  | (62.8 | ) |  |  | — |  |  |  | (1.4 | ) |  |  | — |  |  |  | (57.7 | ) |  |  | — |  |  |  | (0.7 | )
Regulatory classification of certain pension costs |  |  | — |  |  |  | — |  |  |  | — |  |  |  | — |  |  |  | 23.9 |  |  |  | — |  |  |  | 1.1 |  |  |  | — |
Actuarial losses (gains) |  |  | (2.9 | ) |  |  | 0.8 |  |  |  | 0.2 |  |  |  | (0.2 | ) |  |  | (2.2 | ) |  |  | 2.7 |  |  |  | 0.1 |  |  |  | 0.2 |
Benefits paid |  |  | (18.6 | ) |  |  | (14.1 | ) |  |  | — |  |  |  | — |  |  |  | (15.1 | ) |  |  | (11.9 | ) |  |  | — |  |  |  | — |
Ending obligations |  | $ | 303.1 |  |  | $ | 303.7 |  |  | $ | 7.0 |  |  | $ | 5.5 |  |  | $ | 263.9 |  |  | $ | 238.6 |  |  | $ | 1.4 |  |  | $ | — |
Change in plans' assets |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Beginning fair value |  | $ | 243.7 |  |  | $ | 293.0 |  |  | $ | — |  |  | $ | — |  |  | $ | 191.4 |  |  | $ | 238.9 |  |  | $ | — |  |  | $ | — |
Actual return on plans' assets |  |  | 11.8 |  |  |  | 27.6 |  |  |  | — |  |  |  | — |  |  |  | 10.1 |  |  |  | 22.1 |  |  |  | — |  |  |  | — |
Employer contributions |  |  | 10.0 |  |  |  | — |  |  |  | — |  |  |  | 1.4 |  |  |  | 10.0 |  |  |  | — |  |  |  | — |  |  |  | 0.7 |
Regulatory classification of certain pension costs |  |  | — |  |  |  | — |  |  |  | — |  |  |  | — |  |  |  | 15.2 |  |  |  | — |  |  |  | — |  |  |  | — |
Plan settlements |  |  | — |  |  |  | (62.8 | ) |  |  | — |  |  |  | (1.4 | ) |  |  | — |  |  |  | (57.7 | ) |  |  | — |  |  |  | (0.7 | )
Benefits paid |  |  | (18.6 | ) |  |  | (14.1 | ) |  |  | — |  |  |  | — |  |  |  | (15.1 | ) |  |  | (11.9 | ) |  |  | — |  |  |  | — |
Ending fair value |  | $ | 246.9 |  |  | $ | 243.7 |  |  | $ | — |  |  | $ | — |  |  | $ | 211.6 |  |  | $ | 191.4 |  |  | $ | — |  |  | $ | — |
Funded status at end of year |  | $ | (56.2 | ) |  | $ | (60.0 | ) |  | $ | (7.0 | ) |  | $ | (5.5 | ) |  | $ | (52.3 | ) |  | $ | (47.2 | ) |  | $ | (1.4 | ) |  | $ | — |
Accumulated postretirement benefit obligation |  | $ | 289.4 |  |  | $ | 289.5 |  |  | $ | 6.8 |  |  | $ | 4.9 |  |  | $ | 250.2 |  |  | $ | 226.5 |  |  | $ | 1.4 |  |  | $ | — |
For the year ended December 31, 2024, Pension Plan actuarial gains were primarily due to an increased discount rate, partially offset by an increased interest crediting rate. For the year ended December 31, 2023, Pension Plan actuarial losses were primarily due to more lump sum payouts expected, partially offset by demographic experience.
|  | OGE Energy |  |  | OG&E |
|  | Postretirement Benefit Plans |  |  | Postretirement Benefit Plans |
December 31 (In millions) |  | 2024 |  |  | 2023 |  |  | 2024 |  |  | 2023 |
Change in benefit obligation |  |  |  |  |  |  |  |  |  |  |  |
Beginning obligations |  | $ | 103.3 |  |  | $ | 101.9 |  |  | $ | 77.3 |  |  | $ | 76.4 |
Service cost |  |  | 0.1 |  |  |  | 0.1 |  |  |  | 0.1 |  |  |  | 0.1 |
Interest cost |  |  | 5.2 |  |  |  | 5.2 |  |  |  | 3.9 |  |  |  | 3.9 |
Participants' contributions |  |  | 3.5 |  |  |  | 3.4 |  |  |  | 2.4 |  |  |  | 2.4 |
Actuarial losses (gains) |  |  | (3.1 | ) |  |  | 4.9 |  |  |  | (2.1 | ) |  |  | 4.0 |
Regulatory classification of certain pension costs |  |  | — |  |  |  | — |  |  |  | 1.4 |  |  |  | — |
Benefits paid |  |  | (10.9 | ) |  |  | (12.2 | ) |  |  | (8.3 | ) |  |  | (9.5 | )
Ending obligations |  | $ | 98.1 |  |  | $ | 103.3 |  |  | $ | 74.7 |  |  | $ | 77.3 |
Change in plans' assets |  |  |  |  |  |  |  |  |  |  |  |
Beginning fair value |  | $ | 32.7 |  |  | $ | 32.8 |  |  | $ | 29.6 |  |  | $ | 29.8 |
Actual return on plans' assets |  |  | (1.6 | ) |  |  | 1.9 |  |  |  | (1.4 | ) |  |  | 1.7 |
Employer contributions |  |  | 6.3 |  |  |  | 6.8 |  |  |  | 4.9 |  |  |  | 5.2 |
Participants' contributions |  |  | 3.5 |  |  |  | 3.4 |  |  |  | 2.4 |  |  |  | 2.4 |
Benefits paid |  |  | (10.9 | ) |  |  | (12.2 | ) |  |  | (8.3 | ) |  |  | (9.5 | )
Ending fair value |  | $ | 30.0 |  |  | $ | 32.7 |  |  | $ | 27.2 |  |  | $ | 29.6 |
Funded status at end of year |  | $ | (68.1 | ) |  | $ | (70.6 | ) |  | $ | (47.5 | ) |  | $ | (47.7 | )
Schedule of Defined Benefit Plans Disclosures | The following tables present the net periodic benefit cost components, before consideration of capitalized amounts, of OGE Energy's Pension Plan, Restoration of Retirement Income Plan and postretirement benefit plans that are included in the financial statements. Service cost is presented within Other Operation and Maintenance Expense, and the remaining net periodic benefit cost components as listed in the following tables are presented within Other Net Periodic Benefit Income (Expense) in the statements of income. OG&E recovers specific amounts of pension and postretirement medical costs in rates approved in its Oklahoma rate reviews. In accordance with approved orders, OG&E defers the difference between actual pension and postretirement medical expenses and the amount approved in its last Oklahoma rate review as a regulatory asset or regulatory liability. These amounts have been recorded in the Pension tracker in the regulatory assets and liabilities table in Note 1 and within Other Net Periodic Benefit Income (Expense) in the statements of income.
OGE Energy |  | Pension Plan |  |  | Restoration of Retirement Income Plan |
Year Ended December 31 (In millions) |  | 2024 |  |  | 2023 |  |  | 2022 |  |  | 2024 |  |  | 2023 |  |  | 2022 |
Service cost |  | $ | 5.3 |  |  | $ | 5.4 |  |  | $ | 7.6 |  |  | $ | 1.0 |  |  | $ | 1.0 |  |  | $ | 1.1 |
Interest cost |  |  | 15.6 |  |  |  | 15.9 |  |  |  | 15.7 |  |  |  | 0.3 |  |  |  | 0.3 |  |  |  | 0.2 |
Expected return on plan assets |  |  | (16.5 | ) |  |  | (16.2 | ) |  |  | (25.4 | ) |  |  | — |  |  |  | — |  |  |  | — |
Amortization of net loss |  |  | 6.5 |  |  |  | 8.0 |  |  |  | 8.9 |  |  |  | — |  |  |  | — |  |  |  | 0.2 |
Amortization of unrecognized prior service cost (A) |  |  | — |  |  |  | — |  |  |  | — |  |  |  | 0.3 |  |  |  | 0.3 |  |  |  | 0.2 |
Settlement cost |  |  | — |  |  |  | 21.8 |  |  |  | 30.6 |  |  |  | — |  |  |  | 0.5 |  |  |  | 0.3 |
Net periodic benefit cost |  | $ | 10.9 |  |  | $ | 34.9 |  |  | $ | 37.4 |  |  | $ | 1.6 |  |  | $ | 2.1 |  |  | $ | 2.0 |
(A) Unamortized prior service cost is amortized on a straight-line basis over the average remaining service period to the first eligibility age of participants who are expected to receive a benefit and are active at the date of the plan amendment.
OG&E |  | Pension Plan |  |  | Restoration of Retirement Income Plan |
Year Ended December 31 (In millions) |  | 2024 |  |  | 2023 |  |  | 2022 |  |  | 2024 |  |  | 2023 |  |  | 2022 |
Service cost |  | $ | 5.3 |  |  | $ | 4.4 |  |  | $ | 6.2 |  |  | $ | 0.1 |  |  | $ | — |  |  | $ | — |
Interest cost |  |  | 13.4 |  |  |  | 12.6 |  |  |  | 12.1 |  |  |  | 0.1 |  |  |  | — |  |  |  | — |
Expected return on plan assets |  |  | (14.0 | ) |  |  | (12.9 | ) |  |  | (19.6 | ) |  |  | — |  |  |  | — |  |  |  | — |
Amortization of net loss |  |  | 6.2 |  |  |  | 6.9 |  |  |  | 7.4 |  |  |  | — |  |  |  | — |  |  |  | — |
Settlement cost |  |  | — |  |  |  | 20.4 |  |  |  | 12.9 |  |  |  | — |  |  |  | 0.4 |  |  |  | — |
Total net periodic benefit cost |  |  | 10.9 |  |  |  | 31.4 |  |  |  | 19.0 |  |  |  | 0.2 |  |  |  | 0.4 |  |  |  | — |
Plus: Amount allocated from OGE Energy |  |  | — |  |  |  | 3.0 |  |  |  | 5.2 |  |  |  | 1.4 |  |  |  | 1.7 |  |  |  | 1.5 |
Net periodic benefit cost |  | $ | 10.9 |  |  | $ | 34.4 |  |  | $ | 24.2 |  |  | $ | 1.6 |  |  | $ | 2.1 |  |  | $ | 1.5 |
In addition to the net periodic benefit cost amounts recognized, as presented in the table above, for the Pension and Restoration of Retirement Income Plans in 2024, 2023 and 2022, the Registrants recognized the following:
Year Ended December 31 (In millions) |  | 2024 |  |  | 2023 |  |  | 2022 |
Change in pension expense to maintain allowed recoverable amount in Oklahoma jurisdiction (A) |  | $ | 5.8 |  |  | $ | 33.3 |  |  | $ | 15.2 |
Deferral of pension expense related to pension settlement charges included in the above line item: |  |  |  |  |  |  |  |  |
Oklahoma jurisdiction (A) |  | $ | — |  |  | $ | 20.1 |  |  | $ | 15.4 |
Arkansas jurisdiction (A) |  | $ | — |  |  | $ | 1.9 |  |  | $ | 1.4 |
(A) Included in the pension regulatory asset in each jurisdiction, as indicated in the regulatory assets and liabilities table in Note 1.
|  | OGE Energy |  |  | OG&E |
|  | Postretirement Benefit Plans |  |  | Postretirement Benefit Plans |
Year Ended December 31 (In millions) |  | 2024 |  |  | 2023 |  |  | 2022 |  |  | 2024 |  |  | 2023 |  |  | 2022 |
Service cost |  | $ | 0.1 |  |  | $ | 0.1 |  |  | $ | 0.2 |  |  | $ | 0.1 |  |  | $ | 0.1 |  |  | $ | 0.1 |
Interest cost |  |  | 5.2 |  |  |  | 5.2 |  |  |  | 3.5 |  |  |  | 3.9 |  |  |  | 3.9 |  |  |  | 2.7 |
Expected return on plan assets |  |  | (1.6 | ) |  |  | (1.7 | ) |  |  | (1.8 | ) |  |  | (1.4 | ) |  |  | (1.6 | ) |  |  | (1.6 | )
Amortization of net loss (gain) |  |  | (0.2 | ) |  |  | (0.2 | ) |  |  | 1.5 |  |  |  | — |  |  |  | — |  |  |  | 1.5 |
Amortization of unrecognized prior service cost (A) |  |  | — |  |  |  | — |  |  |  | (3.8 | ) |  |  | — |  |  |  | — |  |  |  | (3.6 | )
Total net periodic benefit cost (income) |  |  | 3.5 |  |  |  | 3.4 |  |  |  | (0.4 | ) |  |  | 2.6 |  |  |  | 2.4 |  |  |  | (0.9 | )
Plus: Amount allocated from OGE Energy |  |  |  |  |  |  |  |  |  |  |  | 0.5 |  |  |  | 0.5 |  |  |  | — |
Net periodic benefit cost (income) |  | $ | 3.5 |  |  | $ | 3.4 |  |  | $ | (0.4 | ) |  | $ | 3.1 |  |  | $ | 2.9 |  |  | $ | (0.9 | )
(A) Unamortized prior service cost is amortized on a straight-line basis over the average remaining service period to the first eligibility age of participants who are expected to receive a benefit and are active at the date of the plan amendment. In addition to the net periodic benefit cost or income amounts recognized, as presented in the table above, for the postretirement benefit plans in 2024, 2023 and 2022, the Registrants recognized the following:
Year Ended December 31 (In millions) |  | 2024 |  |  | 2023 |  |  | 2022 |
Change in postretirement expense to maintain allowed recoverable amount in Oklahoma jurisdiction (A) |  | $ | 2.3 |  |  | $ | 4.4 |  |  | $ | 0.6 |
(A) Included in the pension regulatory asset, as indicated in the regulatory assets and liabilities table in Note 1.
Schedule of Capitalized Pension and Postretirement Cost | The following table presents the amount of net periodic benefit cost capitalized and attributable to each of the Registrants for OGE Energy's Pension Plan and postretirement benefit plans in 2024, 2023 and 2022.
|  | OGE Energy |  |  | OG&E |
(In millions) |  | 2024 |  |  | 2023 |  |  | 2022 |  |  | 2024 |  |  | 2023 |  |  | 2022 |
Capitalized portion of net periodic pension benefit cost |  | $ | 2.2 |  |  | $ | 2.2 |  |  | $ | 3.0 |  |  | $ | 2.2 |  |  | $ | 1.9 |  |  | $ | 2.5 |
Capitalized portion of net periodic postretirement benefit cost |  | $ | 0.1 |  |  | $ | 0.1 |  |  | $ | 0.2 |  |  | $ | 0.1 |  |  | $ | 0.1 |  |  | $ | 0.1 |
Schedule of Assumptions Used | Rate Assumptions
|  | Pension Plan and Restoration of Retirement Income Plan |  |  | Postretirement Benefit Plans |
Year Ended December 31 |  | 2024 |  |  | 2023 |  |  | 2022 |  |  | 2024 |  |  | 2023 |  |  | 2022 |
Assumptions to determine benefit obligations: |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Discount rate |  |  | 5.70 | % |  |  | 5.40 | % |  |  | 5.45 | % |  |  | 5.70 | % |  |  | 5.35 | % |  |  | 5.40 | %
Rate of compensation increase |  |  | 4.20 | % |  |  | 4.20 | % |  |  | 4.20 | % |  | N/A |  |  | N/A |  |  | N/A |
Interest crediting rate |  |  | 4.25 | % |  |  | 3.50 | % |  |  | 3.50 | % |  | N/A |  |  | N/A |  |  | N/A |
Assumptions to determine net periodic benefit cost: |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Discount rate |  |  | 5.40 | % |  |  | 5.45 | % |  |  | 4.01 | % |  |  | 5.35 | % |  |  | 5.40 | % |  |  | 2.80 | %
Expected return on plan assets |  |  | 7.00 | % |  |  | 7.00 | % |  |  | 7.00 | % |  |  | 4.00 | % |  |  | 4.00 | % |  |  | 4.00 | %
Rate of compensation increase |  |  | 4.20 | % |  |  | 4.20 | % |  |  | 4.20 | % |  | N/A |  |  | N/A |  |  | N/A |
Interest crediting rate |  |  | 3.50 | % |  |  | 3.50 | % |  |  | 3.50 | % |  | N/A |  |  | N/A |  |  | N/A |
N/A - not applicable
Projected Benefit Obligation Funded Status Thresholds | The Pension Plan assets are held in a trust which follows an investment policy and strategy designed to reduce the funded status volatility of the Plan by utilizing liability driven investing. The purpose of liability-driven investing is to structure the asset portfolio to more closely resemble the pension liability and thereby more effectively hedge against changes in the liability. The investment policy follows a glide path approach that shifts a higher portfolio weighting to fixed income as the Plan's funded status increases. The following table presents the targeted fixed income and equity allocations at different funded status levels.
Projected Benefit Obligation Funded Status Thresholds |  | <90% |  | 95% |  | 100% |  | 105% |  | 110% |  | 115% |  | 120%
Fixed income |  | 50% |  | 58% |  | 65% |  | 73% |  | 80% |  | 85% |  | 90%
Equity |  | 50% |  | 42% |  | 35% |  | 27% |  | 20% |  | 15% |  | 10%
Total |  | 100% |  | 100% |  | 100% |  | 100% |  | 100% |  | 100% |  | 100%
Pension Plan Equity Asset Allocation Table | Within the portfolio's overall allocation to equities, the funds are allocated according to the guidelines in the following table.
Asset Class |  | Target Allocation |  | Minimum |  | Maximum
Domestic Large Cap Equity |  | 40% |  | 35% |  | 60%
Domestic Mid-Cap Equity |  | 15% |  | 5% |  | 25%
Domestic Small-Cap Equity |  | 25% |  | 5% |  | 30%
International Equity |  | 20% |  | 10% |  | 30%
Schedule of Allocation of Plan Assets | The following tables present the postretirement benefit plans' investments that are measured at fair value on a recurring basis at December 31, 2024 and 2023. There were no Level 2 investments held by the postretirement benefit plans at December 31, 2024 and 2023.
(In millions) |  | December 31, 2024 |  |  | Level 1 |  |  | Level 3 |
Group retiree medical insurance contract |  | $ | 13.6 |  |  | $ | — |  |  | $ | 13.6 |
Mutual funds |  |  | 16.4 |  |  |  | 16.4 |  |  |  | — |
Total OGE Energy plan investments |  | $ | 30.0 |  |  | $ | 16.4 |  |  | $ | 13.6 |
Plan investments attributable to affiliates |  |  | (2.8 | ) |  |  |  |  |  |
Total OG&E plan investments |  | $ | 27.2 |  |  |  |  |  |  |
(In millions) |  | December 31, 2023 |  |  | Level 1 |  |  | Level 3 |
Group retiree medical insurance contract |  | $ | 16.8 |  |  | $ | — |  |  | $ | 16.8 |
Mutual funds |  |  | 15.9 |  |  |  | 15.9 |  |  |  | — |
Total OGE Energy plan investments |  | $ | 32.7 |  |  | $ | 15.9 |  |  | $ | 16.8 |
Plan investments attributable to affiliates |  |  | (3.1 | ) |  |  |  |  |  |
Total OG&E plan investments |  | $ | 29.6 |  |  |  |  |  |  |
Schedule of Effect of Significant Unobservable Inputs, Changes in Plan Assets | The following table presents a reconciliation of the postretirement benefit plans' investments that are measured at fair value on a recurring basis using significant unobservable inputs (Level 3).
Year Ended December 31 (In millions) |  | 2024 |
Group retiree medical insurance contract: |  |  |
Beginning balance |  | $ | 16.8 |
Claims paid |  |  | (4.1 | )
Realized losses |  |  | (1.5 | )
Investment fees |  |  | (0.1 | )
Interest income |  |  | 0.6 |
Net unrealized gains related to instruments held at the reporting date |  |  | 1.9 |
Ending balance |  | $ | 13.6 |
Schedule of Expected Benefit Payments | The following table presents the benefit payments the Registrants expect to pay related to the Pension Plan and Restoration of Retirement Income Plan. These expected benefits are based on the same assumptions used to measure the Registrants' benefit obligation at the end of the year and include benefits attributable to estimated future employee service.
(In millions) |  | OGE Energy |  |  | OG&E |
2025 |  | $ | 44.9 |  |  | $ | 40.4 |
2026 |  | $ | 29.7 |  |  | $ | 26.3 |
2027 |  | $ | 35.4 |  |  | $ | 24.9 |
2028 |  | $ | 28.9 |  |  | $ | 24.9 |
2029 |  | $ | 27.4 |  |  | $ | 24.9 |
2030-2034 |  | $ | 127.1 |  |  | $ | 110.5 |
The Medicare Prescription Drug, Improvement and Modernization Act of 2003 expanded coverage for prescription drugs. The following table presents the gross benefit payments the Registrants expect to pay related to the postretirement benefit plans, including prescription drug benefits.
(In millions) |  | OGE Energy |  |  | OG&E |
2025 |  | $ | 13.9 |  |  | $ | 10.5 |
2026 |  | $ | 11.3 |  |  | $ | 8.4 |
2027 |  | $ | 10.3 |  |  | $ | 7.7 |
2028 |  | $ | 9.4 |  |  | $ | 7.1 |
2029 |  | $ | 8.7 |  |  | $ | 6.6 |
2030-2034 |  | $ | 35.6 |  |  | $ | 27.6 |
Defined Benefit Plan, Plan Assets, Category | The following tables present the Pension Plan's investments that are measured at fair value on a recurring basis at December 31, 2024 and 2023. There were no Level 3 investments held by the Pension Plan at December 31, 2024 and 2023.
(In millions) | December 31, 2024 |  |  | Level 1 |  |  | Level 2 |  |  | Net Asset Value (A) |
Common stocks | $ | 55.7 |  |  | $ | 55.7 |  |  | $ | — |  |  | $ | — |
U.S. Treasury notes and bonds (B) |  | 49.3 |  |  |  | 49.3 |  |  |  | — |  |  |  | — |
Mortgage- and asset-backed securities |  | 23.9 |  |  |  | — |  |  |  | 23.9 |  |  |  | — |
Corporate fixed income and other securities |  | 50.3 |  |  |  | — |  |  |  | 50.3 |  |  |  | — |
Commingled fund (C) |  | 13.4 |  |  |  | — |  |  |  | — |  |  |  | 13.4 |
Foreign government bonds |  | 0.3 |  |  |  | — |  |  |  | 0.3 |  |  |  | — |
U.S. municipal bonds |  | 0.1 |  |  |  | — |  |  |  | 0.1 |  |  |  | — |
Money market fund |  | 0.9 |  |  |  | — |  |  |  | — |  |  |  | 0.9 |
Mutual funds |  | 62.0 |  |  |  | 62.0 |  |  |  | — |  |  |  | — |
Preferred stocks |  | 0.5 |  |  |  | 0.5 |  |  |  | — |  |  |  | — |
U.S. Treasury futures: |  |  |  |  |  |  |  |  |  |  |
Cash collateral |  | 0.1 |  |  |  | 0.1 |  |  |  | — |  |  |  | — |
Forward contracts: |  |  |  |  |  |  |  |  |  |  |
Receivable (foreign currency) |  | 0.1 |  |  |  | — |  |  |  | 0.1 |  |  |  | — |
Total Pension Plan investments |  | 256.6 |  |  | $ | 167.6 |  |  | $ | 74.7 |  |  | $ | 14.3 |
Interest and dividends receivable |  | 1.5 |  |  |  |  |  |  |  |  |  |
Receivable from broker for securities sold |  | 9.1 |  |  |  |  |  |  |  |  |  |
Payable to broker for securities purchased |  | (20.3 | ) |  |  |  |  |  |  |  |  |
Total OGE Energy Pension Plan assets | $ | 246.9 |  |  |  |  |  |  |  |  |  |
Pension Plan investments attributable to affiliates |  | (35.3 | ) |  |  |  |  |  |  |  |  |
Total OG&E Pension Plan assets | $ | 211.6 |  |  |  |  |  |  |  |  |  |
(In millions) | December 31, 2023 |  |  | Level 1 |  |  | Level 2 |  |  | Net Asset Value (A) |
Common stocks | $ | 56.9 |  |  | $ | 56.9 |  |  | $ | — |  |  | $ | — |
U.S. Treasury notes and bonds (B) |  | 42.4 |  |  |  | 42.4 |  |  |  | — |  |  |  | — |
Mortgage- and asset-backed securities |  | 22.0 |  |  |  | — |  |  |  | 22.0 |  |  |  | — |
Corporate fixed income and other securities |  | 54.6 |  |  |  | — |  |  |  | 54.6 |  |  |  | — |
Commingled fund (C) |  | 13.8 |  |  |  | — |  |  |  | — |  |  |  | 13.8 |
Foreign government bonds |  | 0.2 |  |  |  | — |  |  |  | 0.2 |  |  |  | — |
U.S. municipal bonds |  | 0.3 |  |  |  | — |  |  |  | 0.3 |  |  |  | — |
Money market fund |  | 1.3 |  |  |  | — |  |  |  | — |  |  |  | 1.3 |
Mutual fund |  | 55.3 |  |  |  | 55.3 |  |  |  | — |  |  |  | — |
Preferred stocks |  | 1.0 |  |  |  | 1.0 |  |  |  | — |  |  |  | — |
U.S. Treasury futures: |  |  |  |  |  |  |  |  |  |  |
Cash collateral |  | 0.3 |  |  |  | 0.3 |  |  |  | — |  |  |  | — |
Forward contracts: |  |  |  |  |  |  |  |  |  |  |
Receivable (foreign currency) |  | 0.1 |  |  |  | — |  |  |  | 0.1 |  |  |  | — |
Total Pension Plan investments |  | 248.2 |  |  | $ | 155.9 |  |  | $ | 77.2 |  |  | $ | 15.1 |
Interest and dividends receivable |  | 1.4 |  |  |  |  |  |  |  |  |  |
Receivable from broker for securities sold |  | 8.3 |  |  |  |  |  |  |  |  |  |
Payable to broker for securities purchased |  | (14.2 | ) |  |  |  |  |  |  |  |  |
Total OGE Energy Pension Plan assets | $ | 243.7 |  |  |  |  |  |  |  |  |  |
Pension Plan investments attributable to affiliates |  | (52.3 | ) |  |  |  |  |  |  |  |  |
Total OG&E Pension Plan assets | $ | 191.4 |  |  |  |  |  |  |  |  |  |
(A) GAAP allows the measurement of certain investments that do not have a readily determinable fair value at the net asset value. These investments do not consider the observability of inputs; therefore, they are not included within the fair value hierarchy. (B) This category represents U.S. Treasury notes and bonds with a Moody's Investors Service rating of Aaa and Government Agency Bonds with a Moody's Investors Service rating of A1 or higher. (C) This category represents units of participation in a commingled fund that primarily invested in stocks of international companies and emerging markets.

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