As of December 31, 2023, we had $18.50 billion of fixed-rate senior unsecured notes (the Notes), including $10.0 billion issued in August 2022 and $8.50 billion issued in May 2023. The following table summarizes the Notes and the carrying amount of our debt (in millions, except percentages):


	Maturity	Stated Interest Rate	Effective Interest Rate	December 31, 2023		December 31, 2022
August 2022 debt:
2027 Notes	2027	3.50%	3.63%	$	2,750	$	2,750
2032 Notes	2032	3.85%	3.92%	3,000		3,000
2052 Notes	2052	4.45%	4.51%	2,750		2,750
2062 Notes	2062	4.65%	4.71%	1,500		1,500

May 2023 debt:
2028 Notes	2028	4.60%	4.68%	1,500
2030 Notes	2030	4.80%	4.90%	1,000
2033 Notes	2033	4.95%	5.00%	1,750
2053 Notes	2053	5.60%	5.64%	2,500
2063 Notes	2063	5.75%	5.79%	1,750
Total face amount of long-term debt				18,500		10,000
Unamortized discount and issuance costs, net				(115)		(77)
Long-term debt				$	18,385	$	9,923

Each series of the Notes in the table above rank equally with each other. Interest on the Notes is payable semi-annually in arrears. We may redeem the Notes at any time, in whole or in part, at specified redemption prices. We are not subject to any financial covenants under the Notes. Interest expense, net of capitalized interest, recognized on the debt was $420 million and $160 million for the years ended December 31, 2023 and 2022, respectively.

The total estimated fair value of our outstanding debt was $18.48 billion and $8.63 billion as of December 31, 2023 and 2022, respectively. The fair value was determined based on the closing trading price per $100 of the Notes and is categorized accordingly as Level 2 in the fair value hierarchy.