Why are there no Depreciation Tables?

Q. Why are there no Depreciation Tables? 

A. The absence of "depreciation tables" in our Replacement Cost Tool is not an oversight but a deliberate choice. Estimating depreciation is a critical component of the appraisal process, and relying on a replacement cost service to provide this information is not sound appraisal practice. USPAP states that when developing a Cost Approach, an appraiser must "analyze such comparable data as are available to estimate the difference between the cost new and the present worth of the improvements (depreciation)." Note the phrase "analyze...comparable data." The market determines the difference between "cost" and "value," and it is the appraiser's responsibility to complete this analysis and estimate depreciation. As experienced appraisers, we thoroughly inspect the property and carefully consider factors such as physical, functional, and external depreciation to determine the property's Effective Age. This puts us in the best position to estimate depreciation accurately. While "straight line" tables provided by other cost services for physical depreciation may seem like a simple solution, academic studies have shown that they can often produce highly inaccurate results. We firmly believe that the appraiser is the expert in determining an accurate "Effective Age estimate" and should not rely on a cost service to provide this information.