Ameresco, Inc. Annual report pursuant to Section 13 and 15(d)

Summary of Significant Accounting Policies (Tables)

12 Months Ended

Dec. 31, 2021

Changes in the allowance for credit losses was as follows:


	Year Ended December 31,
	2021		2020		2019
Allowance for credit loss, beginning of period	$	2,266	$	2,260	$	2,765
Charges to (recoveries of) costs and expenses, net	187		282		(216)
Account write-offs and other	(190)		(276)		(289)
Allowance for credit loss, end of period	$	2,263	$	2,266	$	2,260

Depreciation and amortization of property and equipment are computed on a straight-line basis over the following estimated useful lives:


Asset Classification						Estimated Useful Life
Furniture and office equipment						Five years
Computer equipment and software costs						Three to five years
Leasehold improvements						Lesser of term of lease or five years
Automobiles						Five years
Land						Unlimited

Property and equipment, net consisted of the following:


	December 31,
	2021		2020
Furniture and office equipment	$	3,008	$	2,905
Computer equipment and software costs	17,593		14,531
Leasehold improvements	2,472		2,373
Automobiles	1,419		1,268
Land	6,781		3,041
Property and equipment, gross	31,273		24,118
Less: accumulated depreciation	(18,156)		(15,136)
Property and equipment, net	$	13,117	$	8,982

The following table sets forth our depreciation expense on property and equipment:


	Year Ended December 31,
Location	2021		2020		2019
Selling, general & administrative expenses	$	3,143	$	3,317	$	2,987