Armstrong Inc. is a calendar-year corporation. Its financial statements for the years ended 12/31/20 and 12/31/21 contained the following errors:

	2020	2021
Ending inventory	$15,000 overstatement	$24,000 understatement
Depreciation expense	$6,000 understatement	$12,000 overstatement

Assume that the 2020 errors were not corrected and that no errors occurred in 2019. By what amount will 2020 net income (ignore income taxes) be overstated or understated?

Group of answer choices

$21,000 overstatement

$9,000 overstatement

$21,000 understatement

$9,000 understatement