	December 31, 2018			March 31, 2018
Gross carrying amount	$	51,760		$	50,361
Accumulated amortization		(18,292	)		(24,043	)
Net capitalized software costs	$	33,468		$	26,318

During the nine months ended December 31, 2018, we retired $13,453 of fully amortized capitalized software costs that are no longer being utilized by our client base.

Amortization expense related to capitalized software costs was $2,811 and $1,838 for the three months ended December 31, 2018 and 2017, respectively, and is recorded as cost of revenue in the consolidated statements of comprehensive income.

Amortization expense related to capitalized software costs was $7,703 and $4,409 for the nine months ended December 31, 2018 and 2017, respectively.

The following table presents the remaining estimated amortization of capitalized software costs as of December 31, 2018. The estimated amortization is comprised of (i) amortization of released products and (ii) the expected amortization for products that are not yet available for sale based on their estimated economic lives and projected general release dates.

For the year ended March 31,
2019 (remaining three months)	$	4,900
2020		15,400
2021		8,800
2022		4,368
Total	$	33,468