With changing financial reporting requirements, there is increased interest in the effect of valuation conclusions on financial statements. This document sets forth best practices for the identification of contributory assets and calculation of economic rents. A Toolkit, available for download at this link: https://appraisalfoundation.sharefile.com/share/view/s35c5a865a5042bb9, has been provided as a companion piece to this Advisory to provide additional sample spreadsheets that illustrate application of typical calculations in which contributory asset charges are used.