The purpose of this chapter is to adjust Piketty’s method of estimating long-run trends in wealth-income ratios with net income and savings taking into account natural capital depreciation. In addition, the analysis is extended from Piketty’s original group of eight rich countries to 30 high income economies that are members of the Organization for Economic Cooperation and Development (OECD) over 1970 to 2014. Evidence suggests that growing income and wealth inequality has been pervasive in all OECD economies (OECD 2011), and thus determining whether natural capital depreciation impacts long-run wealth accumulation in these economies may be an important factor underlying this trend.