Retirement Benefits and Trusteed Assets

12 Months Ended

Dec. 31, 2023

Retirement Benefits [Abstract]

Retirement Benefits and Trusteed Assets

RETIREMENT BENEFITS AND TRUSTEED ASSETS

DTE Energy's subsidiary, DTE Energy Corporate Services, LLC, sponsors defined benefit pension plans and other postretirement benefit plans covering certain employees of the Registrants. Plan participants of all plans are solely DTE Energy and affiliate participants.

The table below represents the pension and other postretirement benefit plans of each Registrant at December 31, 2023:

	Registrants
	DTE Energy	DTE Electric
Qualified Pension Plans
DTE Energy Company Retirement Plan	X	X
DTE Gas Company Retirement Plan for Employees Covered by Collective Bargaining Agreements	X
Shenango Inc. Pension Plan(a)	X
Non-qualified Pension Plans
DTE Energy Company Supplemental Retirement Plan(b)	X	X
DTE Energy Company Executive Supplemental Retirement Plan(b)	X	X
DTE Energy Company Supplemental Severance Benefit Plan	X
Other Postretirement Benefit Plans
The DTE Energy Company Comprehensive Non-Health Welfare Plan	X	X
The DTE Energy Company Comprehensive Retiree Group Health Care Plan	X	X
DTE Supplemental Retiree Benefit Plan	X	X
DTE Energy Company Retiree Reimbursement Arrangement Plan	X	X

_____________________________________

(a)Sponsored by Shenango, LLC

(b)Sponsored by DTE Energy Company

DTE Electric participates in various plans that provide pension and other postretirement benefits for DTE Energy and its affiliates. The plans are primarily sponsored by the LLC. DTE Electric accounts for its participation in DTE Energy's qualified and non-qualified pension plans by applying multiemployer accounting. DTE Electric accounts for its participation in other postretirement benefit plans by applying multiple-employer accounting. Within multiemployer and multiple-employer plans, participants pool plan assets for investment purposes and to reduce the cost of plan administration. The primary difference between plan types is that assets contributed in multiemployer plans can be used to provide benefits for all participating employers, while assets contributed within a multiple-employer plan are restricted for use by the contributing employer.

As a result of multiemployer accounting treatment, capitalized costs associated with these plans are reflected in Property, plant, and equipment in DTE Electric's Consolidated Statements of Financial Position. The same capitalized costs are reflected as Regulatory assets and liabilities in DTE Energy's Consolidated Statements of Financial Position. For service costs recognized in earnings, these costs have historically been presented in Operation and maintenance in the Registrants' Consolidated Statements of Operations. For non-service costs recognized in earnings, these costs have historically been presented in Other (Income) and Deductions — Non-operating retirement benefits, net in DTE Energy's Consolidated Statements of Operations and Operation and maintenance in the DTE Electric Consolidated Statements of Operations.

In November 2022, DTE Electric received a rate order from the MPSC approving the deferral of qualified pension plan service and non-service costs that were previously being recognized in earnings. Therefore, the Registrants are recording these costs as Regulatory assets beginning in December 2022.

Pension Plan Benefits

DTE Energy has qualified defined benefit retirement plans for eligible represented and non-represented employees. The plans are noncontributory and provide traditional retirement benefits based on the employee's years of benefit service, average final compensation, and age at retirement. In addition, certain represented and non-represented employees are covered under cash balance provisions that determine benefits on annual employer contributions and interest credits. DTE Energy also maintains supplemental non-qualified, noncontributory, retirement benefit plans for certain management employees. These plans provide for benefits that supplement those provided by DTE Energy’s other retirement plans.

Net pension cost for DTE Energy includes the following components:

	2023		2022		2021
	(In millions)
Service cost	$	57	$	95	$	108
Interest cost	214		166		158
Expected return on plan assets	(352)		(346)		(339)
Amortization of:
Net actuarial loss	7		115		196
Prior service credit	(2)		(1)		—
Settlements	7		94		16
Net pension cost (credit)	$	(69)	$	123	$	139

	2023		2022
	(In millions)
Other changes in plan assets and benefit obligations recognized in Regulatory assets and Other comprehensive income (loss)
Net actuarial loss	$	62	$	156
Amortization of net actuarial loss and settlements	(14)		(209)
Amortization of prior service credit	2		1
Total recognized in Regulatory assets and Other comprehensive income (loss)	$	50	$	(52)
Total recognized in net periodic pension cost, Regulatory assets, and Other comprehensive income (loss)	$	(19)	$	71

The following table reconciles the obligations, assets, and funded status of the plans as well as the amounts recognized as prepaid pension cost or pension liability in DTE Energy's Consolidated Statements of Financial Position at December 31:

	DTE Energy
	2023		2022
	(In millions)
Accumulated benefit obligation, end of year	$	4,089	$	4,078
Change in projected benefit obligation
Projected benefit obligation, beginning of year	$	4,309	$	5,857
Service cost	57		95
Interest cost	214		166
Actuarial (gain) loss	74		(1,252)
Benefits paid	(329)		(278)
Settlements	(7)		(279)
Projected benefit obligation, end of year	$	4,318	$	4,309
Change in plan assets
Plan assets at fair value, beginning of year	$	3,897	$	5,507
Actual return on plan assets	363		(1,062)
Company contributions	36		9
Benefits paid	(329)		(278)
Settlements	(7)		(279)
Plan assets at fair value, end of year	$	3,960	$	3,897
Funded status	$	(358)	$	(412)
Amount recorded as:
Current liabilities	$	(8)	$	(34)
Noncurrent liabilities	(350)		(378)
	$	(358)	$	(412)
Amounts recognized in Accumulated other comprehensive income (loss), pre-tax
Net actuarial loss	$	76	$	85
	$	76	$	85
Amounts recognized in Regulatory assets(a)
Net actuarial loss	$	1,426	$	1,369
Prior service credit	(5)		(7)
	$	1,421	$	1,362

______________________________________

(a)See Note 9 to the Consolidated Financial Statements, "Regulatory Matters."

The increase in DTE Energy's pension benefit obligation for the year ended December 31, 2023 was primarily due to an actuarial loss driven by a decrease in discount rates. The decrease in the pension benefit obligation in 2022 was primarily due to an actuarial gain driven by an increase in discount rates, as well as settlements arising from higher lump-sum payments to retirees during the year.

The Registrants’ policy is to fund pension costs by contributing amounts consistent with the provisions of the Pension Protection Act of 2006, and additional amounts when it deems appropriate. In 2023 and 2022, DTE Gas transferred $50 million of qualified pension plan funds to DTE Electric in exchange for cash consideration. There were no other transfers or contributions made to the qualified pension plans in 2023, 2022, or 2021. DTE Energy does not anticipate making any contributions to the qualified pension plans in 2024, subject to management discretion and any changes in financial market conditions.

DTE Energy's subsidiaries are responsible for their share of qualified and non-qualified pension benefit costs. DTE Electric's allocated portion of pension benefit costs included in regulatory assets and liabilities, operation and maintenance expense, other income and deductions, and capital expenditures was a credit of $39 million for the year ended December 31, 2023, and a cost of $101 million and $107 million for the years ended December 31, 2022 and 2021, respectively. These amounts may include recognized contractual termination benefit charges, curtailment gains, and settlement charges.

At December 31, 2023, the benefits related to DTE Energy's qualified and non-qualified pension plans expected to be paid in each of the next five years and in the aggregate for the five fiscal years thereafter are as follows:

	(In millions)
2024	$	319
2025	328
2026	322
2027	321
2028	324
2029-2033	1,605
Total	$	3,219

Assumptions used in determining the projected benefit obligation and net pension costs of DTE Energy are:

	2023	2022	2021
Projected benefit obligation
Discount rate	5.00%	5.19%	2.91%
Rate of compensation increase	3.80%	3.80%	3.80%
Cash balance interest crediting rate	3.60%	3.40%	2.40%
Net pension costs
Discount rate	5.19%	2.91%	2.57%
Rate of compensation increase	3.80%	3.80%	3.80%
Expected long-term rate of return on plan assets	7.60%	6.80%	7.00%
Cash balance interest crediting rate	3.40%	2.40%	2.00%

DTE Energy employs a formal process in determining the long-term rate of return for various asset classes. Management reviews historic financial market risks and returns and long-term historic relationships between the asset classes of equities, fixed income, and other assets, consistent with the widely accepted capital market principle that asset classes with higher volatility generate a greater return over the long-term. Current market factors such as inflation, interest rates, asset class risks, and asset class returns are evaluated and considered before long-term capital market assumptions are determined. The long-term portfolio return is also established employing a consistent formal process, with due consideration of diversification, active investment management, and rebalancing. Peer data is reviewed to check for reasonableness. As a result of this process, the Registrants have a long-term rate of return assumption for the pension plans of 8.00% for 2024. The Registrants believe this rate is a reasonable assumption for the long-term rate of return on plan assets given the current investment strategy.

The DTE Energy Company Affiliates Employee Benefit Plans Master Trust employs a liability driven investment program whereby the characteristics of plan liabilities are considered when determining investment policy. Risk tolerance is established through consideration of future plan cash flows, plan funded status, and corporate financial considerations. The investment portfolio contains a diversified blend of equity, fixed income, and other investments. Furthermore, equity investments are diversified across U.S. and non-U.S. stocks and large and small market capitalizations. Fixed income investments generally include U.S. Treasuries, other governmental debt, diversified corporate bonds, bank loans, and mortgage-backed securities. Other investments are used to enhance long-term returns while improving portfolio diversification. Derivatives may be utilized in a risk controlled manner, to potentially increase the portfolio beyond the market value of invested assets and/or reduce portfolio investment risk. Investment risk is measured and monitored on an ongoing basis through annual liability measurements, periodic asset/liability studies, and quarterly investment portfolio reviews.

Target allocations for DTE Energy's pension plan assets as of December 31, 2023 are listed below:

U.S. Large Capitalization (Cap) Equity Securities	12	%
U.S. Small Cap and Mid Cap Equity Securities	2
Non-U.S. Equity Securities	11
Fixed Income Securities	48
Hedge Funds and Similar Investments	8
Private Equity and Other	19
	100	%

The following table provides the fair value measurement amounts for DTE Energy's pension plan assets at December 31, 2023 and 2022(a):

	December 31, 2023								December 31, 2022
	Level 1		Level 2		Other(b)		Total		Level 1		Level 2		Other(b)		Total
DTE Energy asset category:	(In millions)
Short-term Investments(c)	$	100	$	—	$	—	$	100	$	77	$	—	$	—	$	77
Equity Securities
Domestic(d)	—		—		550		550		—		—		483		483
International(e)	55		—		309		364		65		—		416		481
Fixed Income Securities
Governmental(f)	531		78		—		609		506		77		—		583
Corporate(g)	—		1,323		—		1,323		—		1,203		—		1,203
Hedge Funds and Similar Investments(h)	104		68		110		282		86		50		185		321
Private Equity and Other(i)	—		—		732		732		—		—		749		749
DTE Energy Total	$	790	$	1,469	$	1,701	$	3,960	$	734	$	1,330	$	1,833	$	3,897

_______________________________________

(a)For a description of levels within the fair value hierarchy, see Note 12 to the Consolidated Financial Statements, "Fair Value."

(b)Amounts represent assets valued at NAV as a practical expedient for fair value.

(c)This category predominantly represents certain short-term fixed income securities and money market investments that are managed in separate accounts or commingled funds. Pricing for investments in this category is obtained from quoted prices in actively traded markets.

(d)This category represents portfolios of large, medium and small capitalization domestic equities. Investments in this category include exchange-traded securities held in a commingled fund classified as NAV assets.

(e)This category primarily consists of portfolios of non-U.S. developed and emerging market equities. Investments in this category include exchange-traded securities for which unadjusted quoted prices can be obtained and exchange-traded securities held in a commingled fund classified as NAV assets.

(f)This category includes U.S. Treasuries, bonds, and other governmental debt. Pricing for investments in this category is obtained from quoted prices in actively traded markets and quotations from broker or pricing services.

(g)This category primarily consists of corporate bonds from diversified industries, bank loans, and mortgage backed securities. Pricing for investments in this category is obtained from quotations from broker or pricing services.

(h)This category utilizes a diversified group of strategies that attempt to capture uncorrelated sources of return and includes publicly traded mutual funds, insurance-linked and asset-backed securities, commingled funds and limited partnership funds. Pricing for mutual funds in this category is obtained from quoted prices in actively traded markets. Pricing for insurance-linked and asset-backed securities is obtained from quotations from broker or pricing services. Commingled funds and limited partnership funds are classified as NAV assets.

(i)This category includes a diversified group of funds and strategies that primarily invests in private equity partnerships. This category also includes investments in private real estate and private debt. All investments in this category are classified as NAV assets.

The pension trust holds debt and equity securities directly and indirectly through commingled funds. Exchange-traded debt and equity securities held directly, as well as publicly traded commingled funds, are valued using quoted market prices in actively traded markets. Non-publicly traded commingled funds hold exchange-traded equity or debt securities and are valued based on stated NAVs. Non-exchange traded fixed income securities are valued by the trustee based upon quotations available from brokers or pricing services. A primary price source is identified by asset type, class, or issue for each security. The trustee monitors prices supplied by pricing services and may use a supplemental price source or change the primary price source of a given security if the trustee challenges an assigned price and determines that another price source is considered preferable. DTE Energy has obtained an understanding of how these prices are derived, including the nature and observability of the inputs used in deriving such prices.

Other Postretirement Benefits

The Registrants participate in defined benefit plans sponsored by the LLC that provide certain other postretirement health care and life insurance benefits for employees who are eligible for these benefits. The Registrants' policy is to fund certain trusts to meet its other postretirement benefit obligations. DTE Energy did not make any contributions to these trusts during 2023 and does not anticipate making any contributions to the trusts in 2024.

DTE Energy and DTE Electric offer a defined contribution VEBA for eligible represented and non-represented employees, in lieu of defined benefit post-employment health care benefits. The Registrants allocate a fixed amount per year to an account in a defined contribution VEBA for each employee. These accounts are managed either by the Registrant (for non-represented and certain represented groups) or by the Utility Workers of America for Local 223 employees. The following table provides contributions to the VEBA in:

	2023		2022		2021
	(In millions)
DTE Energy	$	16	$	16	$	18
DTE Electric	$	7	$	7	$	8

The Registrants also contribute a fixed amount to a Retiree Reimbursement Account for certain non-represented and represented retirees, spouses, and surviving spouses when the youngest of the retiree's covered household becomes eligible for Medicare Part A based on age. The amount of the annual allocation to each participant is determined by the employee's retirement date and increases each year for each eligible participant at the lower of the rate of medical inflation or 2%.

Net other postretirement credit for DTE Energy includes the following components:

	2023		2022		2021
	(In millions)
Service cost	$	17	$	27	$	30
Interest cost	65		48		46
Expected return on plan assets	(111)		(126)		(129)
Amortization of:
Net actuarial loss	10		4		13
Prior service credit	(19)		(19)		(19)
Net other postretirement credit	$	(38)	$	(66)	$	(59)

	2023		2022
	(In millions)
Other changes in plan assets and accumulated postretirement benefit obligation recognized in Regulatory assets and Other comprehensive income (loss)
Net actuarial (gain) loss	$	(17)	$	90
Amortization of net actuarial loss	(10)		(4)
Prior service cost	—		1
Amortization of prior service credit	19		19
Total recognized in Regulatory assets and Other comprehensive income (loss)	$	(8)	$	106
Total recognized in net periodic benefit cost, Regulatory assets, and Other comprehensive income (loss)	$	(46)	$	40

Net other postretirement credit for DTE Electric includes the following components:

	2023		2022		2021
	(In millions)
Service cost	$	13	$	20	$	23
Interest cost	49		37		35
Expected return on plan assets	(73)		(85)		(86)
Amortization of:
Net actuarial loss	1		5		11
Prior service credit	(14)		(14)		(14)
Net other postretirement credit	$	(24)	$	(37)	$	(31)

	2023		2022
	(In millions)
Other changes in plan assets and accumulated postretirement benefit obligation recognized in Regulatory assets
Net actuarial (gain) loss	$	(6)	$	24
Amortization of net actuarial loss	(1)		(5)
Amortization of prior service credit	14		14
Total recognized in Regulatory assets	$	7	$	33
Total recognized in net periodic benefit cost and Regulatory assets	$	(17)	$	(4)

The following table reconciles the obligations, assets, and funded status of the plans including amounts recorded as Accrued postretirement liability in the Registrants' Consolidated Statements of Financial Position at December 31:

	DTE Energy				DTE Electric
	2023		2022		2023		2022
	(In millions)
Change in accumulated postretirement benefit obligation
Accumulated postretirement benefit obligation, beginning of year	$	1,293	$	1,702	$	982	$	1,293
Service cost	17		27		13		20
Interest cost	65		48		49		37
Actuarial (gain) loss	(5)		(395)		2		(301)
Benefits paid	(87)		(89)		(64)		(67)
Accumulated postretirement benefit obligation, end of year	$	1,283	$	1,293	$	982	$	982
Change in plan assets
Plan assets at fair value, beginning of year	$	1,577	$	2,021	$	1,052	$	1,355
Actual return on plan assets	124		(359)		81		(239)
Benefits paid	(87)		(85)		(63)		(64)
Plan assets at fair value, end of year	$	1,614	$	1,577	$	1,070	$	1,052
Funded status	$	331	$	284	$	88	$	70
Amount recorded as:
Noncurrent assets	$	633	$	571	$	378	$	345
Current liabilities	(1)		—		—		—
Noncurrent liabilities	(301)		(287)		(290)		(275)
	$	331	$	284	$	88	$	70
Amounts recognized in Accumulated other comprehensive income (loss), pre-tax
Net actuarial gain	$	(13)	$	(14)	$	—	$	—
Amounts recognized in Regulatory assets(a)
Net actuarial loss	$	173	$	201	$	73	$	80
Prior service credit	(10)		(29)		(6)		(20)
	$	163	$	172	$	67	$	60

______________________________________

(a)See Note 9 to the Consolidated Financial Statements, "Regulatory Matters."

The Registrants' postretirement benefit obligations did not change significantly for the year ended December 31, 2023. The Registrants' postretirement benefit obligations decreased in 2022 primarily due to actuarial gains driven by increases in discount rates.

The following table reflects other postretirement benefit plans with accumulated postretirement benefit obligations in excess of plan assets as of December 31:

	DTE Energy				DTE Electric
	2023		2022		2023		2022
	(In millions)
Accumulated postretirement benefit obligation	$	628	$	625	$	592	$	591
Fair value of plan assets	326		338		302		316
Accumulated postretirement benefit obligation in excess of plan assets	$	302	$	287	$	290	$	275

At December 31, 2023, the benefits expected to be paid, including prescription drug benefits, in each of the next five years and in the aggregate for the five fiscal years thereafter for the Registrants are as follows:

	DTE Energy		DTE Electric
	(In millions)
2024	$	84	$	64
2025	88		67
2026	89		68
2027	91		70
2028	92		71
2029-2033	482		369
Total	$	926	$	709

Assumptions used in determining the accumulated postretirement benefit obligation and net other postretirement benefit costs of the Registrants are:

	2023	2022	2021
Accumulated postretirement benefit obligation
Discount rate	5.00%	5.19%	2.91%
Health care trend rate pre- and post- 65	7.75 / 8.25%	6.75 / 7.25%	6.75 / 7.25%
Ultimate health care trend rate	4.50%	4.50%	4.50%
Year in which ultimate reached pre- and post- 65	2035	2035	2034
Other postretirement benefit costs
Discount rate	5.19%	2.91%	2.58%
Expected long-term rate of return on plan assets	7.20%	6.40%	6.70%
Health care trend rate pre- and post- 65	6.75 / 7.25%	6.75 / 7.25%	6.75 / 7.25%
Ultimate health care trend rate	4.50%	4.50%	4.50%
Year in which ultimate reached pre- and post- 65	2035	2034	2033

The process used in determining the long-term rate of return on assets for the other postretirement benefit plans is similar to that previously described for the pension plans. As a result of this process, the Registrants have a long-term rate of return assumption for the other postretirement benefit plans of 7.60% for 2024. The Registrants believe this rate is a reasonable assumption for the long-term rate of return on plan assets given the current investment strategy.

The DTE Energy Company Master VEBA Trust employs a liability driven investment program whereby the characteristics of plan liabilities are considered when determining investment policy. Risk tolerance is established through consideration of future plan cash flows, plan funded status, and corporate financial considerations. The investment portfolio contains a diversified blend of equity, fixed income, and other investments. Furthermore, equity investments are diversified across U.S. and non-U.S. stocks and large and small market capitalizations. Fixed income investments generally include U.S. Treasuries, other governmental debt, diversified corporate bonds, bank loans, and mortgage-backed securities. Other investments are used to enhance long-term returns while improving portfolio diversification. Derivatives may be utilized in a risk controlled manner to potentially increase the portfolio beyond the market value of invested assets and/or reduce portfolio investment risk. Investment risk is measured and monitored on an ongoing basis through annual liability measurements, periodic asset/liability studies, and quarterly investment portfolio reviews.

Target allocations for the Registrants' other postretirement benefit plan assets as of December 31, 2023 are listed below:

U.S. Large Cap Equity Securities	5	%
Non-U.S. Equity Securities	4
Fixed Income Securities	61
Hedge Funds and Similar Investments	9
Private Equity and Other	21
	100	%

The following tables provide the fair value measurement amounts for the Registrants' other postretirement benefit plan assets at December 31, 2023 and 2022(a):

	December 31, 2023								December 31, 2022
	Level 1		Level 2		Other(b)		Total		Level 1		Level 2		Other(b)		Total
	(In millions)
DTE Energy asset category:
Short-term Investments(c)	$	41	$	—	$	—	$	41	$	35	$	—	$	—	$	35
Equity Securities
Domestic(d)	—		—		76		76		—		—		78		78
International(e)	7		—		43		50		9		—		61		70
Fixed Income Securities
Governmental(f)	242		31		—		273		264		32		—		296
Corporate(g)	—		459		212		671		—		396		194		590
Hedge Funds and Similar Investments(h)	18		21		86		125		31		22		94		147
Private Equity and Other(i)	—		—		378		378		—		—		361		361
DTE Energy Total	$	308	$	511	$	795	$	1,614	$	339	$	450	$	788	$	1,577
DTE Electric asset category:
Short-term Investments(c)	$	27	$	—	$	—	$	27	$	23	$	—	$	—	$	23
Equity Securities
Domestic(d)	—		—		48		48		—		—		50		50
International(e)	4		—		27		31		5		—		39		44
Fixed Income Securities
Governmental(f)	161		21		—		182		178		21		—		199
Corporate(g)	—		302		145		447		—		262		134		396
Hedge Funds and Similar Investments(h)	11		14		58		83		20		15		63		98
Private Equity and Other(i)	—		—		252		252		—		—		242		242
DTE Electric Total	$	203	$	337	$	530	$	1,070	$	226	$	298	$	528	$	1,052

_______________________________________

(a)For a description of levels within the fair value hierarchy see Note 12 to the Consolidated Financial Statements, "Fair Value."

(b)Amounts represent assets valued at NAV as a practical expedient for fair value.

(c)This category predominantly represents certain short-term fixed income securities and money market investments that are managed in separate accounts or commingled funds. Pricing for investments in this category is obtained from quoted prices in actively traded markets.

(d)This category represents portfolios of large, medium and small capitalization domestic equities. Investments in this category include exchange-traded securities held in a commingled fund classified as NAV assets.

(e)This category primarily consists of portfolios of non-U.S. developed and emerging market equities. Investments in this category include exchange-traded securities for which unadjusted quoted prices can be obtained and exchange-traded securities held in a commingled fund classified as NAV assets.

(f)This category includes U.S. Treasuries, bonds and other governmental debt. Pricing for investments in this category is obtained from quoted prices in actively traded markets and quotations from broker or pricing services.

(g)This category primarily consists of corporate bonds from diversified industries, bank loans, and mortgage backed securities. Pricing for investments in this category is obtained from quotations from broker or pricing services. Non-exchange traded securities and exchange-traded securities held in commingled funds are classified as NAV assets.

(h)This category utilizes a diversified group of strategies that attempt to capture uncorrelated sources of return and includes publicly traded mutual funds, insurance-linked and asset-backed securities, commingled funds and limited partnership funds. Pricing for mutual funds in this category is obtained from quoted prices in actively traded markets. Pricing for insurance-linked and asset-backed securities is obtained from quotations from broker or pricing services. Commingled funds and limited partnership funds are classified as NAV assets.

(i)This category includes a diversified group of funds and strategies that primarily invests in private equity partnerships. This category also includes investments in private real estate and private debt. All investments in this category are classified as NAV assets.

The DTE Energy Company Master VEBA Trust holds debt and equity securities directly and indirectly through commingled funds. Exchange-traded debt and equity securities held directly, as well as publicly traded commingled funds, are valued using quoted market prices in actively traded markets. Non-publicly traded commingled funds hold exchange-traded equity or debt securities and are valued based on NAVs. Non-exchange traded fixed income securities are valued by the trustee based upon quotations available from brokers or pricing services. A primary price source is identified by asset type, class, or issue for each security. The trustee monitors prices supplied by pricing services and may use a supplemental price source or change the primary price source of a given security if the trustee challenges an assigned price and determines that another price source is considered preferable. The Registrants have obtained an understanding of how these prices are derived, including the nature and observability of the inputs used in deriving such prices.

Defined Contribution Plans

The Registrants also sponsor defined contribution retirement savings plans. Participation in one of these plans is available to substantially all represented and non-represented employees. For substantially all employees, the Registrants match employee contributions up to certain predefined limits based upon eligible compensation and the employee’s contribution rate. Additionally, for eligible represented and non-represented employees who do not participate in the Pension Plans, the Registrants contribute amounts equivalent to 4% (8% for certain DTE Gas represented employees) of an employee's eligible compensation to the employee's defined contribution retirement savings plan. For DTE Energy, the cost of these plans was $75 million, $73 million, and $70 million for the years ended December 31, 2023, 2022, and 2021, respectively. For DTE Electric, the cost of these plans was $35 million for the years ended December 31, 2023 and 2022 and $34 million for the year ended December 31, 2021.