Because of a mistake in computing depreciation expense, Albatross Company overstated its depreciation expense. It recorded $20 million of depreciation expense in 2019 and $20 million of depreciation expense in 2020. The actual depreciation expense should have been $10 million annually. Albatross Company's auditor discovered this error in 2021. Prepare the adjusting journal entry on December 31, 2021 to correct the error.