							Initial
	October 3,			December 28,			Useful Life
	2020			2019			(in years)
	(in thousands)
Goodwill	$	328,425		$	277,600		indefinite

Other intangible assets:
Trade names (indefinite-lived)	$	140,841		$	148,841		indefinite

Customer relationships and customer-related assets		201,547			200,647		<1-10
Trade name (amortizable)		22,200			-		15
Developed technology		5,600			3,000		6-10
Non-compete agreement		3,338			1,668		2-5
Software license		590			590		2
Less: Accumulated amortization		(112,908	)		(98,784	)

Subtotal		120,367			107,121

Other intangible assets, net	$	261,208		$	255,962

Goodwill at December 28, 2019	$	277,600
Increase related to the acquisition of NewSouth		50,825

Goodwill at October 3, 2020	$	328,425

Trade names at December 28, 2019	$	148,841
Impairment of WWS trade name		(8,000	)

Tradenames at October 3, 2020	$	140,841

Estimated amortization of our amortizable intangible assets for future years is as follows:

Amortization expense relating to amortizable intangible assets for the three months ended October 3, 2020, and September 28, 2019, was $4.7 million and $3.9 million, respectively. Amortization expense relating to amortizable intangible assets for the nine months ended October 3, 2020, and September 28, 2019, was $14.1 million and $12.0 million, respectively.

We perform our annual goodwill and indefinite-lived intangible asset impairment testing on the first day of our fiscal fourth quarter of each year, and at interim periods if needed based on occurrence of triggering events. Given the general deterioration in economic and market conditions associate with the COVID-19 pandemic, and the narrow excess of fair value over carrying value of our WinDoor and WWS trade names as described in our 2019 Annual Report on Form 10-K, the Company determined it should complete interim quantitative impairment tests of its WinDoor and WWS trade names as of as of the end of the Company’s first quarter of 2020. These interim impairment tests did not indicate that impairments of those assets existed at that time.

Following an increase in net sales of 14.0% in the first quarter of 2020, compared to the first quarter of last year, net sales at our WWS reporting unit decreased 19.3% in the second quarter of 2020, compared to the second quarter of last year. As a result of the decrease in net sales during our second quarter of 2020, compared to the second quarter of last year, as well as continued deterioration in macro-economic conditions in our core western markets relating to the COVID-19 pandemic, we determined to complete a second interim impairment test of our WWS trade name as of July 4, 2020. For this second interim impairment test, we further decreased our modeling assumptions for net sales of our WWS reporting unit for our 2020 fiscal year based on a reassessment of our key assumptions in our modeling, including an updated assessment of macro industry growth in our WWS reporting unit’s key markets. We also decreased our 2021 growth rate assumption as we expect the challenging macro-economic conditions in our core western markets to continue during 2021. Based on our revised modeling, we concluded that the fair value of our WWS trade name was less than its carrying value, which resulted in an impairment of our WWS trade name of $8.0 million in our second quarter of 2020.

The rate of decrease in sales at our WWS reporting unit slowed during the third quarter of 2020, decreasing just 4.6% in the third quarter of 2020, compared to last year’s third quarter, which was within our modeling assumptions used during our second impairment test of our WWS trade name as of July 4, 2020. As such, we concluded that it was not necessary to update our impairment test as of October 3, 2020.

For our WWS reporting unit, our most recent annual impairment test of goodwill was a quantitative assessment. Based on this quantitative assessment, we concluded that it was not more likely than not that the carrying value of our WWS reporting unit exceeded its fair value, as the estimated fair value of our WWS reporting unit substantially exceeded the carrying value at that time. Because of the decrease in sales at our WWS reporting unit and continued deterioration in macro-economic conditions in our core western markets relating to the COVID-19 pandemic as described above, we determined to update the projections in our most recent quantitative assessment of WWS reporting unit to goodwill using the sales projections in our WWS trade name impairment assessment that is discussed above. Based on this update of the most recent quantitative assessment, the amount by which the estimated fair value of our WWS reporting unit exceeds its carrying value has decreased, but such fair value was still estimated to be approximately 10% more than its carrying value. As such, we have concluded that it continues to be not more likely than not that the carrying value of our WWS reporting unit exceeds its fair value. However, should our WWS reporting unit experience future financial results which are below our most recently updated projections, the amount by which the estimated fair value of our WWS reporting unit exceeds the carrying value would further decrease, which could result in an impairment of the goodwill of our WWS reporting unit.