Other assets consist of the following (in thousands):


	June 30, 2025		December 31, 2024
Costs to obtain contracts - Customer Agreements	$	2,320,654	$	2,084,545
Costs to obtain contracts - incentives	2,481		2,481
Accumulated amortization of costs to obtain contracts	(288,923)		(243,989)
Unbilled receivables	814,700		681,823
Allowance for credit loss on unbilled receivables	(8,259)		(6,928)
Equity investment	81,297		81,297
Operating lease right-of-use assets	70,813		76,810
Other assets	289,633		345,707
Total	$	3,282,396	$	3,021,746

The Company recorded amortization of costs to obtain contracts of $23.3 million and $17.3 million for the three months ended June 30, 2025 and 2024, respectively, and $45.4 million and $34.3 million for the six months ended June 30, 2025 and 2024, respectively, in Sales and marketing in the consolidated statements of operations.

The majority of unbilled receivables arise from fixed price escalators included in the Company’s long-term Customer Agreements. The escalator is included in calculating the total estimated transaction value for an individual Customer Agreement. The total estimated transaction value is then recognized over the term of the Customer Agreement. The amount of unbilled receivables increases while billings for an individual Customer Agreement are less than the revenue recognized for that Customer Agreement. Conversely, the amount of unbilled receivables decreases once the billings become higher than the amount of revenue recognized in the period. At the end of the initial term of a Customer Agreement, the cumulative amounts recognized as revenue and billed to date are the same, therefore the unbilled receivable balance for an individual Customer Agreement will be zero. The Company applies an estimated loss-rate in order to determine the current expected credit loss for unbilled receivables. The estimated loss-rate is determined by analyzing historical credit losses, residential first and second mortgage foreclosures and consumers’ utility default rates, as well as current economic conditions. The Company reviews individual customer collection status of electricity billings to determine whether the unbilled receivables for an individual customer should be written off, including the possibility of a service transfer to a potential new homeowner.