During the three months ended June 30, 2021, the increase in the Company’s goodwill primarily related to the acquisitions of the remaining 51% interest in Euro Infrastructure Co. and of RigNet on April 30, 2021 (see Note 12 – Acquisitions for more information) and an insignificant effect of foreign currency translation recorded within all three of the Company’s segments. During the three months ended June 30, 2020, the insignificant increase in the Company’s goodwill related to the effects of foreign currency translation recorded within all three of the Company’s segments.

Other acquired intangible assets are amortized using the straight-line method over their estimated useful lives of two to 12 years (which approximates the economic pattern of benefit). Amortization expense related to other acquired intangible assets was $5.9 million and $1.6 million for the three months ended June 30, 2021 and 2020, respectively.

The expected amortization expense of amortizable acquired intangible assets may change due to the effects of foreign currency fluctuations as a result of international businesses acquired. Current and expected amortization expense for acquired intangible assets for each of the following periods is as follows:

	Amortization
	(In thousands)
For the three months ended June 30, 2021	$	5,929

Expected for the remainder of fiscal year 2022	$	23,756
Expected for fiscal year 2023		31,673
Expected for fiscal year 2024		30,123
Expected for fiscal year 2025		27,848
Expected for fiscal year 2026		27,696
Thereafter		120,845
	$	261,941

In the first quarter of fiscal year 2022, the gross amount and accumulated amortization for acquired identifiable intangible assets were reduced by the retirement of fully amortized assets that were no longer in use.