At year-end, Ed Company has a balance of $10,000 in accounts receivable of which $1,000 is more than 30 days overdue. Ed has a credit balance of $100 in the allowance for doubtful accounts before any year-end adjustments. Using the aging of accounts receivable method, Ed estimates that 1% of current accounts and 10% of accounts over thirty days are uncollectible. What is the amount of bad debt expense?