For the years ended December 31, 2022, 2021, and 2020, the Company recorded $843.8 million, $612.4 million and $455.9 million, respectively, of net product revenues. Three individual customers accounted for 48%, 33% and 7% of net product revenues for the year ended December 31, 2022, 48%, 39% and 10% for the year ended December 31, 2021 and 47%, 39% and 11% for the year ended December 31, 2020. The Company considers there to be revenue concentration risks for regions where net product revenues exceed 10% of consolidated net product revenues. The concentration of the Company’s net product revenues within a particular region may have a material adverse effect on the Company’s revenues and results of operations if sales in the respective regions experience difficulties. For the year ended December 31, 2022, net product revenues totaled $747.1 million and $96.7 million within the United States and the rest of the world, respectively, with no individual rest of world country or region exceeding 10% of total net product revenues. Net product revenues within the United States exceeded 90% of total net product revenues for each of the years ended December 31, 2021 and 2020, respectively.

As of December 31, 2022 and 2021, the Company's accounts receivable were $214.6 million and $153.0 million, respectively, both of which were related to product sales receivable, net of discounts and allowances. Three individual customers accounted for 36%, 35% and 12% of accounts receivable from product sales for the year ended December 31, 2022 and 41%, 41% and 10% for the year ended December 31, 2021. As of December 31, 2022, the Company believes that such customers are of high credit quality.

The following table summarizes an analysis of the change in reserves for discounts and allowances for the periods indicated:


	Chargebacks			Rebates			Prompt Pay			Other Accruals			Total
	(in thousands)
Balance, as of December 31, 2020	$	2,281		$	41,771		$	1,949		$	4,969		$	50,970
Provision		13,308			78,637			9,400			16,107			117,452
Payments/credits		(14,790	)		(59,902	)		(8,551	)		(14,713	)		(97,956	)
Balance, as of December 31, 2021	$	799		$	60,506		$	2,798		$	6,363		$	70,466
Provision		12,446			102,835			12,904			47,684			175,869
Payments/credits		(12,828	)		(95,848	)		(12,359	)		(30,602	)		(151,637	)
Balance, as of December 31, 2022	$	417		$	67,493		$	3,343		$	23,445		$	94,698

The following table summarizes the total reserves above included in the Company’s consolidated balance sheets for the periods indicated:


	As of December 31,
	2022		2021
	(in thousands)
Reduction to accounts receivable	$	25,914	$	8,321
Component of accrued expenses		68,784		62,145
Total reserves	$	94,698	$	70,466