Abstract
Lund (2002a) showed in a CAPM-type model how tax depreciation schedules
affect required expected returns after taxes. Even without leverage higher tax rates
implied lower betas when tax deductions were risk free. Here they are risky, and
marginal investment is taxed together with inframarginal in an analytical model
of decreasing returns. With imperfect loss offset tax claims are analogous to call
options. The beta of equity is still decreasing in the tax rate, but increasing in the
underlying volatility. The results are important if market data are used to infer
required expected returns, and in discussions of tax design.
Keywords: Corporate tax, depreciation, imperfect loss offset, decreasing returns,
cost of capital, uncertainty
