No. Although ROE is always computed as income/invested capital, no agreement exists concerning the definition of either the numerator or the denominator.
For the numerator, Offtoa uses Income After Taxes. However, other valid computations of ROE use (a) EBITDA or (b) EBIT.
For the denominator, Offtoa uses Total Shareholder Equity. However, other valid computations of ROE use (a) Long-Term Debt plus Total Shareholder Equity, (b) Total Liabilities plus Total Shareholder Equity, (c) Long-Term Debt plus Total Shareholder Equity less Preferred Shares, (d) Total Liabilities plus Total Shareholder Equity less Preferred Shares. The argument for including debt is that for many start-up companies, debt is convertible debt, and thus is equivalent to equity.
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