Residual Income Model (RIM)

The residual income model (RIM), also called the excess earnings model or economic value added (EVA) approach to equity valuation, determines intrinsic value by adding the present value of expected future residual income to the current book value of equity. Residual income is the profit remaining after deducting a charge for the cost of equity capital: Residual Income = Net Income - (Equity × Cost of Equity). Only earnings above the required return on equity create value.

The formula is: Intrinsic Value = Book Value + Σ (Residual Income_t / (1 + r)^t), where r is the cost of equity. In practice, analysts forecast residual income for an explicit period (5-10 years) and then add a terminal value representing residual income in perpetuity. If a company earns exactly its cost of equity, residual income is zero and the stock should trade at book value. Companies that consistently earn above their cost of equity (like high-ROIC businesses) are worth a premium to book value.

The RIM has several advantages over traditional DCF: it anchors the valuation to observable book value (reducing reliance on speculative terminal values), it works well for financial institutions where cash flow-based models are problematic, and terminal value typically represents a smaller portion of total value (reducing estimation risk). It's particularly favored for valuing banks and insurance companies, where book value is meaningful and cash flows are difficult to define. The model is also used in academic research because it directly links accounting data to value creation. Limitations include sensitivity to accounting policies (aggressive revenue recognition or asset capitalization inflates book value), the challenge of estimating the cost of equity precisely, and the assumption that clean surplus accounting holds (all gains/losses flow through the income statement).