The purpose of deprecation is to utilize the matching principle. Matching the use of the equipment or asset (expense) to the revenue earned from the use. There are four types GAAP-allowed methods of deprecation. a) Straight-line Methodb) Units of Production Methodc) Sum of the Years Digitsd) Declining Balance MethodI find the Sum of the Years Digits method to be the most confusing. I do not seem to understand how this method would accurately articulate the true deprecation. I under the theory of more being deprecation in the first year and less each year following. I do not understand how this would be the best method to use. I think the Units of Production Method would actually be the first choice, and the second choice would be the straight line. Which method do you think would be the most accurate?