Using the aging method of accounts receivable method, $5,700 of the company’s Accounts Receivable are estimated to be uncollectible. At the end of the year, the balance of Accounts Receivable is $107,000 and the unadjusted credit balance of the Allowance for Doubtful Accounts is $640. Credit sales during the year totaled $164,000. What is the current year’s Bad Debt Expense?