The Peridot Company purchased machinery on January 2, 2019, for $800,000. A five-year life was estimated and no residual value was anticipated. Peridot decided to use the straight-line depreciation method and recorded $160,000 in depreciation in 2019 and 2020. Early in 2021, the company revised the total estimated life of the machinery to eight years. Required: 1. What type of change is this? 2. Is Peridot required to revise prior years’ financial statements as a result of the change? 3. Is Peridot required to provide a disclosure note to report the change? 4. Determine depreciation for 2021.