The components of property, plant, and equipment were as follows (dollars in millions):


	June 30,			December 31,
	2025			2024
Land and land improvements	$	216.4		$	203.4
Buildings		1,234.3			1,140.0
Machinery and equipment		7,547.0			7,368.8
Construction in progress		350.9			397.2
Other		200.2			195.8
Property, plant and equipment, at cost		9,548.8			9,305.2
Less accumulated depreciation		(5,432.9	)		(5,266.2	)
Property, plant, and equipment, net	$	4,115.9		$	4,039.0

Depreciation expense for the three months ended June 30, 2025 and 2024 was $130.8 million and $118.7 million, respectively. During the six months ended June 30, 2025 and 2024, depreciation expense was $258.9 million and $236.8 million, respectively. During the six months ended June 30, 2025, we recognized $3.6 million of incremental depreciation expense as a result of closure costs related to corrugated products facilities. We recognized $1.5 million of incremental depreciation expense during the six months ended June 30, 2024 as a result of Jackson mill conversion-related activities.

At June 30, 2025 and December 31, 2024, purchases of property, plant, and equipment included in accounts payable were $64.8 million and $33.8 million, respectively.