Our property, plant and equipment, net, consisted of the following (in millions):


	December 31, 2024		December 31, 2023
Machinery, equipment, vehicles and office furniture	$	18,339	$	16,309
Land and buildings	10,677		9,498
AI infrastructure	5,152		1,510
Tooling	3,883		3,129
Leasehold improvements	3,688		3,136
Computer equipment, hardware and software	2,902		2,409
Construction in progress	6,783		5,791
	51,424		41,782
Less: Accumulated depreciation	(15,588)		(12,057)
Total	$	35,836	$	29,725

Construction in progress is primarily comprised of ongoing construction and expansion of our facilities, equipment and tooling related to the manufacturing of our products as well as AI-related assets which have not yet been placed in service. Completed assets are transferred to their respective asset classes and depreciation begins when an asset is ready for its intended use.

Depreciation expense during the years ended December 31, 2024, 2023 and 2022 was $4.12 billion, $3.33 billion and $2.42 billion, respectively.