The changes in the carrying amount of goodwill for the nine months ended September 30, 2023 are as follows (in millions):


Balance, as of December 31, 2022
Goodwill	$	6,980
Accumulated impairment losses		(2,814	)
		4,166
Goodwill acquired as part of acquisitions during current year		17
Goodwill allocated to hospitals divested or held-for-sale		(240	)
Balance, as of September 30, 2023
Goodwill		6,757
Accumulated impairment losses		(2,814	)
	$	3,943

Goodwill is allocated to each identified reporting unit, which is defined as an operating segment or one level below the operating segment (referred to as a component of the entity). Management has determined that the Company’s operating segment meets the criteria to be classified as a reporting unit.

Goodwill is evaluated for impairment annually and when an event occurs or circumstances change that, more likely than not, reduce the fair value of the reporting unit below its carrying value. The Company performed its last annual goodwill impairment evaluation during the fourth quarter of 2022 using an October 31, 2022 measurement date, which indicated no impairment.

The Company estimates the fair value of the reporting unit using both a discounted cash flow model as well as a market multiple model. The cash flow forecasts are adjusted by an appropriate discount rate based on the Company’s estimate of a market participant’s weighted-average cost of capital. These models are both based on the Company’s best estimate of future revenues and operating costs and are reconciled to the Company’s consolidated market capitalization, with consideration of the amount a potential acquirer would be required to pay, in the form of a control premium, in order to gain sufficient ownership to set policies, direct operations and control management decisions.

The determination of fair value in the Company’s goodwill impairment analysis is based on an estimate of fair value for the reporting unit utilizing known and estimated inputs at the evaluation date. Some of those inputs include, but are not limited to, the most recent price of the Company’s common stock and fair value of long-term debt, the Company’s recent financial results, estimates of future revenue and expense growth, estimated market multiples, expected capital expenditures, income tax rates, costs of invested capital and a discount rate.

Future estimates of fair value could be adversely affected if the actual outcome of one or more of the assumptions described above changes materially in the future, including as a result of any decline in the Company’s stock price and the fair value of its long-term debt, an increase in the volatility of the Company’s stock price and the fair value of its long-term debt, lower-than-expected hospital volumes and/or net operating revenues, higher market interest rates, increased operating costs or other adverse impacts on the Company’s financial results. Such changes impacting the calculation of fair value could result in a material impairment charge in the future.

The determination of fair value of the Company’s hospital operations reporting unit as part of its goodwill impairment measurement represents a Level 3 fair value measurement in the fair value hierarchy due to its use of internal projections and unobservable measurement inputs.