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Pension Benefit Obligations | 12 Months Ended
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Sep. 30, 2023
Pension Benefit Obligations |
Pension Benefit Obligations | 7. Pension Benefit Obligations In the U.S., the Company sponsors various qualified defined benefit pension plans. Benefits under these plans generally are based on the employee’s years of creditable service and compensation; however, all U.S. defined benefit plans are closed to new participants and have frozen accruals. The Company also sponsors various non-qualified plans in the U.S.; all of these plans are frozen. Outside the U.S., the Company sponsors various pension plans, which are appropriate to the country in which the Company operates, some of which are government mandated. The following tables provide reconciliations of the changes in the U.S. and international plans’ benefit obligations, reconciliations of the changes in the fair value of assets for the last three years ended September 30, and reconciliations of the funded status as of September 30 of each year. ​
​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​
​ | ​ | Fiscal Year Ended
​ | ​ | September 30, | ​ | September 30, | ​ | September 30,
​ | ​ | 2023 | ​ | 2022 | ​ | 2021
​ |  | U.S. |  | Int’l |  | U.S. |  | Int’l |  | U.S. |  | Int’l
​ | ​ | (in millions)
Change in benefit obligation: | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​
Benefit obligation at beginning of year | ​ | $ | 198.1 | ​ | $ | 791.2 | ​ | $ | 265.4 | ​ | $ | 1,470.8 | ​ | $ | 283.9 | ​ | $ | 1,440.3
Service cost | ​ |  | — | ​ |  | 0.3 | ​ |  | — | ​ |  | 0.5 | ​ |  | — | ​ |  | 0.5
Participant contributions | ​ |  | 0.1 | ​ |  | 0.2 | ​ |  | 0.1 | ​ |  | 0.3 | ​ |  | 0.1 | ​ |  | 0.3
Interest cost | ​ |  | 9.8 | ​ |  | 47.7 | ​ |  | 4.7 | ​ |  | 24.1 | ​ |  | 4.3 | ​ |  | 21.6
Benefits and expenses paid | ​ |  | (17.2) | ​ |  | (42.2) | ​ |  | (18.4) | ​ |  | (44.3) | ​ |  | (18.5) | ​ |  | (48.6)
Actuarial (gain) loss | ​ |  | (8.8) | ​ |  | (112.5) | ​ |  | (51.9) | ​ |  | (458.1) | ​ |  | (3.7) | ​ |  | (4.7)
Plan settlements | ​ |  | (1.5) | ​ |  | (1.5) | ​ |  | (1.8) | ​ |  | (2.2) | ​ |  | (0.7) | ​ |  | (5.9)
Transfers in | ​ | ​ | 0.7 | ​ | ​ | — | ​ | ​ | — | ​ | ​ | — | ​ | ​ | — | ​ | ​ | —
Plan amendments | ​ | ​ | — | ​ | ​ | — | ​ | ​ | — | ​ | ​ | — | ​ | ​ | — | ​ | ​ | 0.4
Foreign currency translation (gain) loss | ​ |  | — | ​ |  | 73.0 | ​ |  | — | ​ |  | (199.9) | ​ |  | — | ​ |  | 66.9
Benefit obligation at end of year | ​ | $ | 181.2 | ​ | $ | 756.2 | ​ | $ | 198.1 | ​ | $ | 791.2 | ​ | $ | 265.4 | ​ | $ | 1,470.8
​
​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​
​ | ​ | Fiscal Year Ended
​ | ​ | September 30, | ​ | September 30, | ​ | September 30,
​ | ​ | 2023 | ​ | 2022 | ​ | 2021
​ |  | U.S. |  | Int’l |  | U.S. |  | Int’l |  | U.S. |  | Int’l
​ | ​ | (in millions)
Change in plan assets | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​
Fair value of plan assets at beginning of year | ​ | $ | 101.4 | ​ | $ | 683.5 | ​ | $ | 138.9 | ​ | $ | 1,251.8 | ​ | $ | 129.6 | ​ | $ | 1,166.2
Actual return on plan assets | ​ |  | 7.8 | ​ |  | (54.2) | ​ |  | (27.2) | ​ |  | (374.5) | ​ |  | 14.7 | ​ |  | 61.1
Employer contributions | ​ |  | 8.2 | ​ |  | 24.8 | ​ |  | 9.8 | ​ |  | 23.6 | ​ |  | 13.7 | ​ |  | 25.2
Participant contributions | ​ |  | 0.1 | ​ |  | 0.2 | ​ |  | 0.1 | ​ |  | 0.3 | ​ |  | 0.1 | ​ |  | 0.3
Benefits and expenses paid | ​ |  | (17.2) | ​ |  | (42.2) | ​ |  | (18.4) | ​ |  | (44.3) | ​ |  | (18.5) | ​ |  | (48.6)
Plan settlements | ​ |  | (1.5) | ​ |  | (1.5) | ​ |  | (1.8) | ​ |  | (2.2) | ​ |  | (0.7) | ​ |  | (5.9)
Foreign currency translation (loss) gain | ​ |  | — | ​ |  | 62.7 | ​ |  | — | ​ |  | (171.2) | ​ |  | — | ​ |  | 53.5
Fair value of plan assets at end of year | ​ | $ | 98.8 | ​ | $ | 673.3 | ​ | $ | 101.4 | ​ | $ | 683.5 | ​ | $ | 138.9 | ​ | $ | 1,251.8
​
​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​
​ | ​ | Fiscal Year Ended
​ | ​ | September 30, 2023 | ​ | September 30, 2022 | ​ | September 30, 2021
​ |  | U.S. |  | Int’l |  | U.S. |  | Int’l |  | U.S. |  | Int’l
​ | ​ | (in millions)
Reconciliation of funded status: | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​
Funded status at end of year | ​ | $ | (82.4) | ​ | $ | (82.9) | ​ | $ | (96.7) | ​ | $ | (107.7) | ​ | $ | (126.5) | ​ | $ | (219.0)
Contribution made after measurement date | ​ |  | N/A | ​ |  | N/A | ​ |  | N/A | ​ |  | N/A | ​ |  | N/A | ​ |  | N/A
Net amount recognized at end of year | ​ | $ | (82.4) | ​ | $ | (82.9) | ​ | $ | (96.7) | ​ | $ | (107.7) | ​ | $ | (126.5) | ​ | $ | (219.0)
​ The following table sets forth the amounts recognized in the consolidated balance sheets as of September 30, 2023, 2022 and 2021: ​
​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​
​ | ​ | Fiscal Year Ended
​ | ​ | September 30, 2023 | ​ | September 30, 2022 | ​ | September 30, 2021
​ |  | U.S. |  | Int’l |  | U.S. |  | Int’l |  | U.S. |  | Int’l
​ | ​ | (in millions)
Amounts recognized in the consolidated balance sheets: | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​
Other non-current assets | ​ | $ | — | ​ | $ | 38.7 | ​ | $ | — | ​ | $ | 36.8 | ​ | $ | — | ​ | $ | 47.5
Accrued expenses and other current liabilities | ​ |  | (8.4) | ​ |  | — | ​ |  | (8.6) | ​ |  | — | ​ |  | (9.1) | ​ |  | —
Pension benefit obligations | ​ |  | (74.0) | ​ |  | (121.6) | ​ |  | (88.1) | ​ |  | (144.5) | ​ |  | (117.4) | ​ |  | (266.5)
Net amount recognized in the balance sheet | ​ | $ | (82.4) | ​ | $ | (82.9) | ​ | $ | (96.7) | ​ | $ | (107.7) | ​ | $ | (126.5) | ​ | $ | (219.0)
​ The following table details the reconciliation of amounts in the consolidated statements of stockholders’ equity for the fiscal years ended September 30, 2023, 2022 and 2021: ​
​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​
​ | ​ | Fiscal Year Ended
​ | ​ | September 30, 2023 | ​ | September 30, 2022 | ​ | September 30, 2021
​ |  | U.S. |  | Int’l |  | U.S. |  | Int’l |  | U.S. |  | Int’l
​ | ​ | (in millions)
Reconciliation of amounts in consolidated statements of stockholders’ equity: | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​
Prior service cost | ​ | $ | (0.1) | ​ | $ | (1.2) | ​ | $ | (0.1) | ​ | $ | (1.2) | ​ | $ | (0.1) | ​ | $ | (1.6)
Net loss | ​ |  | (77.5) | ​ | ​ | (207.1) | ​ | ​ | (91.7) | ​ | ​ | (187.1) | ​ | ​ | (116.5) | ​ | ​ | (279.5)
Total recognized in accumulated other comprehensive loss | ​ | $ | (77.6) | ​ | $ | (208.3) | ​ | $ | (91.8) | ​ | $ | (188.3) | ​ | $ | (116.6) | ​ | $ | (281.1)
​ The components of net periodic benefit cost other than the service cost component are included in other income in the consolidated statement of operations. The following table details the components of net periodic benefit cost for the Company’s pension plans for fiscal years ended September 30, 2023, 2022 and 2021: ​
​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​
​ | ​ | Fiscal Year Ended
​ | ​ | September 30, 2023 | ​ | September 30, 2022 | ​ | September 30, 2021
​ |  | U.S. |  | Int’l |  | U.S. |  | Int’l |  | U.S. |  | Int’l
​ | ​ | (in millions)
Components of net periodic benefit cost: | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​
Service costs | ​ | $ | — | ​ | $ | 0.3 | ​ | $ | — | ​ | $ | 0.5 | ​ | $ | — | ​ | $ | 0.5
Interest cost on projected benefit obligation | ​ |  | 9.8 | ​ | ​ | 47.7 | ​ | ​ | 4.7 | ​ | ​ | 24.1 | ​ | ​ | 4.3 | ​ | ​ | 21.6
Expected return on plan assets | ​ |  | (5.8) | ​ | ​ | (60.8) | ​ | ​ | (5.6) | ​ | ​ | (41.4) | ​ | ​ | (6.5) | ​ | ​ | (43.5)
Amortization of prior service costs | ​ | ​ | — | ​ | ​ | 0.1 | ​ | ​ | — | ​ | ​ | 0.1 | ​ | ​ | — | ​ | ​ | 0.1
Amortization of net loss (gain) | ​ | ​ | 3.5 | ​ | ​ | (0.6) | ​ | ​ | 5.6 | ​ | ​ | 6.9 | ​ | ​ | 5.9 | ​ | ​ | 9.2
Settlement (gain) loss recognized | ​ | ​ | (0.1) | ​ | ​ | 0.2 | ​ | ​ | 0.2 | ​ | ​ | 0.3 | ​ | ​ | 0.2 | ​ | ​ | 0.8
Net periodic benefit cost (credit) | ​ | $ | 7.4 | ​ | $ | (13.1) | ​ | $ | 4.9 | ​ | $ | (9.5) | ​ | $ | 3.9 | ​ | $ | (11.3)
​ The amount of applicable deferred income taxes included in other comprehensive income arising from a change in net prior service cost and net gain/loss was $3.1 million, $18.8 million, and $9.3 million in the years ended September 30, 2023, 2022 and 2021, respectively. Amounts included in accumulated other comprehensive loss as of September 30, 2023 that are expected to be recognized as components of net periodic benefit cost during fiscal 2024 are (in millions): ​
​ | ​ | ​ | ​ | ​ | ​ | ​
​ |  | U.S. |  | Int’l
Amortization of prior service cost | ​ | $ | — | ​ | $ | (0.1)
Amortization of net actuarial (losses) gain | ​ |  | (3.1) | ​ |  | 2.3
Total | ​ | $ | (3.1) | ​ | $ | 2.2
​ The table below provides additional year-end information for pension plans with accumulated benefit obligations in excess of plan assets. ​
​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​
​ | ​ | Fiscal Year Ended
​ | ​ | September 30, | ​ | September 30, | ​ | September 30,
​ | ​ | 2023 | ​ | 2022 | ​ | 2021
​ |  | U.S. |  | Int’l |  | U.S. |  | Int’l |  | U.S. |  | Int’l
​ | ​ | (in millions)
Projected benefit obligation | ​ | $ | 168.8 | ​ | $ | 628.1 | ​ | $ | 184.8 | ​ | $ | 601.4 | ​ | $ | 247.8 | ​ | $ | 1,248.8
Accumulated benefit obligation | ​ | $ | 168.8 | ​ | $ | 628.1 | ​ | $ | 184.8 | ​ | $ | 600.1 | ​ | $ | 247.8 | ​ | $ | 1,243.9
Fair value of plan assets | ​ | $ | 98.8 | ​ | $ | 506.5 | ​ | $ | 101.4 | ​ | $ | 456.9 | ​ | $ | 138.9 | ​ | $ | 982.4
​ Funding requirements for each pension plan are determined based on the local laws of the country where such pension plan resides. In certain countries, the funding requirements are mandatory while in other countries, they are discretionary. The Company currently intends to contribute $22.2 million to the international plans in fiscal 2024. The required minimum contributions for U.S. plans are not significant. In addition, the Company may make discretionary contributions. The Company currently intends to contribute $12.9 million to U.S. plans in fiscal 2024. The table below provides the expected future benefit payments, in millions: ​
​ | ​ | ​ | ​ | ​ | ​ | ​
Year Ending September 30, |  | U.S. |  | Int’l
2024 | ​ | $ | 20.2 | ​ | $ | 47.1
2025 | ​ |  | 19.3 | ​ | ​ | 45.0
2026 | ​ |  | 19.1 | ​ | ​ | 46.3
2027 | ​ |  | 18.1 | ​ | ​ | 47.8
2028 | ​ | ​ | 17.4 | ​ | ​ | 49.3
2029-2033 | ​ |  | 74.3 | ​ | ​ | 267.6
Total | ​ | $ | 168.4 | ​ | $ | 503.1
​ The underlying assumptions for the pension plans are as follows: ​
​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​
​ | ​ | Fiscal Year Ended |
​ | ​ | September 30, | ​ | September 30, | ​ | September 30, |
​ | ​ | 2023 | ​ | 2022 | ​ | 2021 |
​ |  | U.S. |  | Int’l |  | U.S. |  | Int’l |  | U.S. |  | Int’l |
​ | ​ | (in millions) | ​
Weighted-average assumptions to determine benefit obligation: | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​
Discount rate |  | 5.76 | % | 5.65 | % | 5.40 | % | 5.27 | % | 2.46 | % | 1.98 | %
Salary increase rate |  | N/A | ​ | 3.06 | % | N/A | ​ | 3.48 | % | N/A | ​ | 3.13 | %
Weighted-average assumptions to determine net periodic benefit cost: | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​
Discount rate |  | 5.40 | % | 5.27 | % | 2.46 | % | 1.98 | % | 2.20 | % | 1.67 | %
Salary increase rate |  | N/A | ​ | 3.48 | % | N/A | ​ | 3.13 | % | N/A | ​ | 2.68 | %
Expected long-term rate of return on plan assets |  | 7.00 | % | 6.04 | % | 6.25 | % | 3.93 | % | 6.80 | % | 3.95 | %
​ Pension costs are determined using the assumptions as of the beginning of the plan year. The funded status is determined using the assumptions as of the end of the plan year. The following table summarizes the Company’s target allocation for 2023 and pension plan asset allocation, both U.S. and international, as of September 30, 2023 and 2022: ​
​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​
​ | ​ | ​ | ​ | Percentage of Plan Assets |
​ | ​ | ​ | ​ | ​ | ​ | as of September 30, |
​ | ​ | Target Allocations | ​ | 2023 | ​ | 2022 |
​ |  | U.S. |  | Int’l |  | U.S. |  | Int’l |  | U.S. |  | Int’l |
Asset Category: | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​
Equities |  | 32 | % | 27 | % | 33 | % | 24 | % | 36 | % | 20 | %
Debt |  | 58 | ​ | 61 | ​ | 56 | ​ | 62 | ​ | 48 | ​ | 47 | ​
Cash |  | 2 | ​ | — | ​ | 2 | ​ | 4 | ​ | 5 | ​ | 15 | ​
Property and other |  | 8 | ​ | 12 | ​ | 9 | ​ | 10 | ​ | 11 | ​ | 18 | ​
Total |  | 100 | % | 100 | % | 100 | % | 100 | % | 100 | % | 100 | %
​ The Company’s domestic and foreign plans seek a competitive rate of return relative to an appropriate level of risk depending on the funded status and obligations of each plan and typically employ both active and passive investment management strategies. The Company’s risk management practices include diversification across asset classes and investment styles and periodic rebalancing toward asset allocation targets. The target asset allocation selected for each plan reflects a risk/return profile that the Company believes is appropriate relative to each plan’s liability structure and return goals. To develop the expected long-term rate of return on assets assumption, the Company considered the historical returns and the future expectations for returns for each asset class, as well as the target asset allocation of the pension portfolio and the diversification of the portfolio. This resulted in the selection of a 7.00% and 6.04% weighted-average long-term rate of return on assets assumption for the fiscal year ended September 30, 2023 for U.S. and non-U.S. plans, respectively. As of September 30, 2023, the fair values of the Company’s pension plan assets by major asset categories were as follows: ​
​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​
​ | ​ | ​ | ​ | Fair Value Measurement as of | ​ | ​ | ​
​ | ​ | ​ | ​ | September 30, 2023 | ​ | ​ | ​
​ | ​ | Total | ​ | Quoted | ​ | Significant | ​ | ​ | ​ | ​ | ​
​ | ​ | Carrying | ​ | Prices in | ​ | Other | ​ | Significant | ​ | ​ | ​
​ | ​ | Value as of | ​ | Active | ​ | Observable | ​ | Unobservable | ​ | Investments
​ | ​ | September 30, | ​ | Markets | ​ | Inputs | ​ | Inputs | ​ | measured at
​ |  | 2023 |  | (Level 1) |  | (Level 2) |  | (Level 3) |  | NAV
​ | ​ | (in millions)
Cash and cash equivalents | ​ | $ | 29.5 | ​ | $ | 20.2 | ​ | $ | 9.3 | ​ | $ | — | ​ | $ | —
Debt securities | ​ | ​ | 338.3 | ​ | ​ | 338.3 | ​ | ​ | — | ​ | ​ | — | ​ | ​ | —
Investment funds: | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​
Diversified and equity funds | ​ |  | 43.5 | ​ |  | 30.3 | ​ |  | 13.2 | ​ |  | — | ​ |  | —
Fixed income funds | ​ |  | 26.1 | ​ |  | 21.7 | ​ |  | 4.4 | ​ |  | — | ​ |  | —
Common collective funds | ​ | ​ | 372.0 | ​ | ​ | — | ​ | ​ | — | ​ | ​ | — | ​ | ​ | 372.0
Derivative instruments | ​ | ​ | (37.3) | ​ | ​ | 1.5 | ​ | ​ | (38.8) | ​ | ​ | — | ​ | ​ | —
Total | ​ | $ | 772.1 | ​ | $ | 412.0 | ​ | $ | (11.9) | ​ | $ | — | ​ | $ | 372.0
​ As of September 30, 2022, the fair values of the Company’s pension plan assets by major asset categories were as follows: ​
​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​
​ | ​ | ​ | ​ | ​ | Fair Value Measurement as of | ​ | ​ | ​
​ | ​ | ​ | ​ | ​ | September 30, 2022 | ​ | ​ | ​
​ | ​ | Total | ​ | Quoted | ​ | Significant | ​ | ​ | ​ | ​ | ​
​ | ​ | Carrying | ​ | Prices in | ​ | Other | ​ | Significant | ​ | ​ | ​
​ | ​ | Value as of | ​ | Active | ​ | Observable | ​ | Unobservable | ​ | Investments
​ | ​ | September 30, | ​ | Markets | ​ | Inputs | ​ | Inputs | ​ | measured at
​ |  | 2022 |  | (Level 1) |  | (Level 2) |  | (Level 3) |  | NAV
​ | ​ | (in millions)
Cash and cash equivalents | ​ | $ | 104.8 | ​ | $ | 99.0 | ​ | $ | 5.8 | ​ | $ | — | ​ | $ | —
Debt securities | ​ | ​ | 339.1 | ​ | ​ | 339.1 | ​ | ​ | — | ​ | ​ | — | ​ | ​ | —
Investment funds: | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​
Diversified and equity funds | ​ |  | 22.2 | ​ |  | 7.3 | ​ |  | 14.9 | ​ |  | — | ​ |  | —
Fixed income funds | ​ |  | 7.9 | ​ |  | 5.7 | ​ |  | 2.2 | ​ |  | — | ​ |  | —
Common collective funds | ​ | ​ | 451.6 | ​ | ​ | — | ​ | ​ | — | ​ | ​ | — | ​ | ​ | 451.6
Derivative instruments | ​ | ​ | (140.7) | ​ | ​ | — | ​ | ​ | (140.7) | ​ | ​ | — | ​ | ​ | —
Total | ​ | $ | 784.9 | ​ | $ | 451.1 | ​ | $ | (117.8) | ​ | $ | — | ​ | $ | 451.6
​ Changes for the year ended September 30, 2022 in the fair value of the Company’s recurring post-retirement plan Level 3 assets are as follows: ​
​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​
​ |  | ​ |  | Actual return |  | Actual return |  | ​ |  | ​ |  | ​ |  | ​
​ | ​ | ​ | ​ | on plan assets, | ​ | on plan assets, | ​ | ​ | ​ | ​ | ​ | Change | ​ | ​
​ | ​ | September 30, | ​ | relating to | ​ | relating to | ​ | ​ | ​ | Transfer | ​ | due to | ​ | ​ | ​
​ | ​ | 2021 | ​ | assets still | ​ | assets sold | ​ | Purchases, | ​ | into / | ​ | exchange | ​ | September 30,
​ | ​ | Beginning | ​ | held at | ​ | during the | ​ | sales and | ​ | (out of) | ​ | rate | ​ | 2022
​ | ​ | balance | ​ | reporting date | ​ | period | ​ | settlements | ​ | Level 3 | ​ | changes | ​ | Ending balance
​ | ​ | (in millions)
Level 3 Assets | ​ | $ | 4.0 | ​ | $ | — | ​ | $ | (0.2) | ​ | $ | (3.5) | ​ | $ | — | ​ | $ | (0.3) | ​ | $ | —
​ Cash equivalents are mostly comprised of short-term money-market instruments and are valued at cost, which approximates fair value. For investment funds not traded on an active exchange, or if the closing price is not available, the trustee obtains indicative quotes from a pricing vendor, broker, or investment manager. These funds are categorized as Level 2 if the custodian obtains corroborated quotes from a pricing vendor or categorized as Level 3 if the custodian obtains uncorroborated quotes from a broker or investment manager. Fixed income investment funds, not traded on an active exchange, categorized as Level 2 are valued by the trustee using pricing models that use verifiable observable market data (e.g., interest rates and yield curves observable at commonly quoted intervals), bids provided by brokers or dealers, or quoted prices of securities with similar characteristics. Hedge funds categorized as Level 3 are valued based on valuation models that include significant unobservable inputs and cannot be corroborated using verifiable observable market data. Hedge funds are valued by independent administrators. Depending on the nature of the assets, the general partners or independent administrators use both the income and market approaches in their models. The market approach consists of analyzing market transactions for comparable assets while the income approach uses earnings or the net present value of estimated future cash flows adjusted for liquidity and other risk factors. As of September 30, 2023, there were no material changes to the valuation techniques. Common collective funds are valued based on net asset value (NAV) per share or unit as a practical expedient as reported by the fund manager, multiplied by the number of shares or units held as of the measurement date. Accordingly, these NAV-based investments have been excluded from the fair value hierarchy. These collective investment funds have redemption notice periods and are redeemable at the NAV, less transaction fees. There are no significant unfunded commitments related to these investments. Multiemployer Pension Plans The Company participates in construction-industry multiemployer pension plans. Generally, the plans provide defined benefits to substantially all employees covered by collective bargaining agreements. Under the Employee Retirement Income Security Act, a contributor to a multiemployer plan is liable, upon termination or withdrawal from a plan, for its proportionate share of a plan’s unfunded vested liability. The Company’s aggregate contributions to these multiemployer plans were $3.0 million and $2.9 million for the years ended September 30, 2023 and 2022, respectively. At September 30, 2023 and 2022, none of the plans in which the Company participates are individually significant to its consolidated financial statements.

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