at the beginning of 2018, uptown travel inc. has the following account balances:

Accounts receivable: $41000 (debit)

Allowance for Bad Debts: $8000 (credit)

During the year, credit sales were $820000. Cash collected in credit sales was $770000, and $16000 was written off. Uptown uses the aging of receivables method to record bad debts expense. The amount estimated as uncollectible was $30000. The amount of bad debts expense for 2018 is ____?