Accounts receivable, net

12 Months Ended

Dec. 31, 2020

Accounts receivable, net.

Accounts receivable, net

4. Accounts receivable, net

	December 31,
	2020		2019
Trade accounts receivable	$	21,422,782	$	22,862,706
Receivable from OC-BVI		62,171		10,808
Other accounts receivable		269,133		222,381
		21,754,086		23,095,895
Allowance for doubtful accounts		(270,110)		(142,236)
Accounts receivable, net	$	21,483,976	$	22,953,659

The activity for the allowance for doubtful accounts consisted of:

	December 31,
	2020		2019
Opening allowance for doubtful accounts	$	142,236	$	158,902
Provision for doubtful accounts		129,107		—
Accounts written off during the year		(1,233)		(16,666)
Ending allowance for doubtful accounts	$	270,110	$	142,236

Significant concentrations of credit risk are disclosed in Note 18.