6. Property, Plant and Equipment, net

Property, plant and equipment, net, including equipment under finance lease obligations and capitalized software development costs, consisted of the following:

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For the years ended December 31, 2023, 2022 and 2021 total depreciation expense was $12.8 million, $9.2 million and $11.5 million, respectively.

Property and equipment under finance lease obligations, consisting of computer equipment, totaled $17.8 million and $12.3 million as of December 31, 2023 and 2022, respectively. As of December 31, 2023 and 2022, accumulated depreciation related to property and equipment under finance lease obligations totaled $12.9 million and $11.2 million, respectively, refer to Footnote 7, Leases.

During the year ended December 31, 2022, the Company disposed of certain office furniture, equipment and leasehold improvements resulting in a loss on disposal of $1.4 million. The fixed asset disposals relate primarily to the transfer of fixed assets in a sublease office arrangement and the abandonment of fixed assets no longer in use. The loss on disposal was recorded in General and administrative expenses in the accompanying Consolidated Statements of Operations and Comprehensive Income.

There were no impairments of Property, plant and equipment identified during the years ended December 31, 2023, 2022 and 2021.