5. Vessels, Net


			Accumulated
	Cost		depreciation		Net book Value
Balance, April 1, 2017	$	1,728,769,295	$	(125,300,048)	$	1,603,469,247
Other additions		218,685		—		218,685
Depreciation		—		(64,576,099)		(64,576,099)
Balance, March 31, 2018	$	1,728,987,980	$	(189,876,147)	$	1,539,111,833
Other additions		4,005,830		—		4,005,830
Depreciation		—		(64,597,349)		(64,597,349)
Balance, March 31, 2019	$	1,732,993,810	$	(254,473,496)	$	1,478,520,314

Additions to vessels, net mainly consisted of the installment payments on the purchase of scrubbers for ten of our VLGCs and other capital improvements to our VLGCs during the year ended March 31, 2019. Our vessels, with a total carrying value of $1,478.5 million and $1,539.1 million as of March 31, 2019 and 2018, respectively, are first‑priority mortgaged as collateral for our long-term debt (refer to Note 9 below). No impairment loss was recorded for the periods presented.