The sum-of-the-years' digits method of depreciation can keep the cost of fixed assets roughly the same from year to year, right? The answer is right, but can you tell me why?

Personal opinion, for reference only

For this question, you must first understand what usage cost is. Obviously, the usage cost in your question is not an accounting concept. We will explain it in the standards and There is no relevant statement in the textbooks of the Note Society. This is probably a concept used in a certain book.

To support your answer, our understanding of usage costs can only include maintenance costs and depreciation costs. Under this premise, we can explain it reasonably. Using the sum of years' digits method, more depreciation is provided in the early period and less in the later period. The depreciation is on a downward trend. However, due to the increase in the service life of the asset, its maintenance costs show an upward trend. One rises and the other falls, which can ensure the maintenance cost of each year. The cost of use is about the same.

The main reason is that the concept of usage cost is a bit confusing. There is no explanation. Who knows what it is.