	Software & Subscription Services		Telematics Products		LoJack U.S. SVR Products			Total
Balance as of February 29, 2020	$	55,132	$	39,180	$	12,023		$	106,335
Impairment loss		-		-		(12,023	)	$	(12,023	)
Effect of exchange rate change on goodwill		305		-		-			305
Balance as of February 28, 2021	$	55,437	$	39,180	$	-		$	94,617

		Gross										Accumulated Amortization						Net
	Useful Life	Feb. 29, 2020		Currency Adjustments			Impair- ment			Feb. 28, 2021		Feb. 29, 2020		Expense		Feb. 28, 2021		Feb. 29, 2020		Feb. 28, 2021
Developed technology (1)	4-6 years	$	27,363		109			(478	)	$	26,994	$	21,437		2,620	$	24,057	$	5,926	$	2,937
Tradenames	10 years		30,093		164			-			30,257		16,303		2,125		18,428		13,790		11,829
Customer lists	4-7 years		25,304		-			-			25,304		22,903		48		22,951		2,401		2,353
Dealer and customer relationships (1)	10-15 years		34,139		(217	)		(1,005	)		32,917		10,753		2,149		12,902		23,386		20,015
Patents	5 years		589		-			-			589		197		38		235		392		354
		$	117,488	$	56		$	(1,483	)	$	116,061	$	71,593	$	6,980	$	78,573	$	45,895	$	37,488

Intangible assets with finite lives are amortized on a straight-line basis over the expected period to be benefited by future cash flows. We monitor and assess these assets for impairment on a periodic basis. Our assessment includes various new product lines and services, which leverage the existing intangible assets as well as consideration of historical and projected revenues and cash flows. In both fiscal 2021 and 2020, we determined that the prolonged secular decline in legacy LoJack US SVR products revenue coupled with the slower than anticipated market penetration of our telematics solutions in the U.S. automotive dealership channel represented determinate indications of impairment. As a result, we performed an assessment of the carrying amount of the related intangible assets supporting these products including the LoJack tradename and dealer and customer relationships. Our assessment of the future cash flows generated by these assets concluded that an impairment loss was present. For the fiscal year ended February 28, 2021, we recorded an impairment loss aggregating $1.5 million, which was attributable to $1.0 million of US Dealer relationships and $0.5 million of developed technology. For the fiscal year ended February 29, 2020, we recorded an impairment loss aggregating $17.7 million, which was attributable to $11.5 million of the LoJack Tradename and $6.2 million of US Dealer relationships. $1.5 million and $12.0 million of these impairment losses are included within Net loss from discontinued operations for fiscal years ended February 28/29, 2021 and 2020, respectively.

Amortization expense of intangible assets from continuing operations was $4.8 million, $5.9 million and $3.9 million in fiscal years ended, February 28/29, 2021, 2020 and 2019, respectively.

Estimated future amortization expense as of February 28, 2021 is as follows (in thousands):