Margaret Moore, CEO of Carla Vista Industries, is concerned about the recent volatility in the company's operating income. She believes that since the number of units sold has been fairly stable over the past three years that operating income also should have been stable. Margaret asked Joseph Taylor, Carla Vista's inventory manager, to help her understand the issue. Joseph reviewed the company's records and compiled the following changes to Finished Goods Inventory (in units) for the years 2019, 2020, and 2021. Year 2019 2020 2021 Beginning inventory 1,000 2,000 500 Production 40,000 38,000 40,000 Sales (39,000) (39,500) (39,500) Ending inventory 2,000 500 1,000 Joseph also gathered the 2019 income statements prepared using absorption costing and variable costing, which follow.