NOTE 5 — Property and Equipment, Net

Our property and equipment consists of the following:



	December 31,
	2018			2017
	(In millions)
Capitalized software development	$	2,643		$	2,111
Computer equipment	597			658
Furniture and other equipment	94			85
Buildings and leasehold improvements	435			283
Land	129			129
	3,898			3,266
Less: accumulated depreciation	(2,552		)	(2,056		)
Projects in progress	531			365
Property and equipment, net	$	1,877		$	1,575

As of December 31, 2018 and 2017, our recorded capitalized software development costs, net of accumulated amortization, which have been placed in service were $829 million and $735 million. For the years ended December 31, 2018, 2017 and 2016, we recorded amortization of capitalized software development costs of $479 million, $398 million and $300 million, most of which is included in technology and content expenses.

As of December 31, 2018, property and equipment, net included build-to-suit assets of $152 million primarily within buildings and leasehold improvements and $111 million as of December 31, 2017 within projects in progress. During the years ended December 31, 2018, 2017 and 2016, we capitalized $44 million, $66 million and $38 million of non-cash construction costs incurred by the landlord related to build-to-suit assets, with a corresponding liability recorded in other long-term liabilities, with the current portion recorded in accrued expenses and other current liabilities.

During 2015, we acquired our future corporate headquarters for $229 million, consisting of multiple office and lab buildings located in Seattle, Washington. We have subsequently spent approximately $30 million in 2016, approximately $70 million in 2017 and approximately $190 million in 2018 relating to the build out of our headquarters. The acquired building assets and related expenditures are included in projects in process and will begin depreciating when the costs incurred related to the build out of the headquarters are complete and the building assets are ready for their intended use, which we estimate to start at the end of 2019.

As of December 31, 2018, 2017 and 2016, we had $55 million, $22 million and $30 million, respectively, included in accounts payable for the acquisition of property and equipment, which is considered a non-cash investing activity in the consolidated statements of cash flows.