

	December 31, 2019		December 31, 2018
Homes completed or under construction	$	314,966	$	268,763
Land and lots - developed and under development	437,553		399,809
Land held for sale	1,048		389
Total inventory	$	753,567	$	668,961

A summary of interest costs incurred, capitalized and expensed is as follows (in thousands):



	Years Ended December 31,
	2019			2018			2017
Interest capitalized at beginning of period	$	14,780		$	10,474		$	9,417
Interest incurred	12,140			9,003			4,456
Interest charged to cost of revenues	(8,324		)	(4,697		)	(3,399		)
Interest capitalized at end of period	$	18,596		$	14,780		$	10,474

As of December 31, 2019, the Company reviewed the performance and outlook for all of its communities for indicators of potential impairment and performed detailed impairment analysis when necessary. As of December 31, 2019, the Company performed further impairment analysis of the selling communities with indicators of impairment with a combined corresponding carrying value of approximately $11.2 million.

For the years ended December 31, 2019, 2018 and 2017, the Company recorded impairment adjustments of $0.1 million, $0.1 million, and $0.1 million, respectively, to reduce the carrying value of impaired communities to fair value. The recorded impairment adjustments related to real estate inventory in our builder operations segments and were included in cost of residential units in our consolidated statements of income.

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