Extending the Basel II approach to estimate capital requirements for equity investments
Under the Basel II banking regulatory capital regime the capital requirements for credit exposures are calculated using the Asymptotic Single Risk Factor (ASRF) approach. The capital requirement is taken to be the contribution of an exposure to the unexpected loss on the bank's diversified portfolio. Here we extend this approach to calculate capital requirements for equity investments. We show that in the case when asset values have a normal distribution an analytical formula for the unexpected loss contribution may be developed. We show that the capital requirements for equity investments are quite different to those of credit exposures, since equity investments can suffer substantial loss of value even when the underlying company has not defaulted. Unexpected loss is commonly used as a measure of capital requirements, but it ignores the ability of earnings to absorb loss. We propose a definition of capital requirement that recognises the expected earnings on assets, and show how to combine the ASRF model and the Capital Asset Pricing Model to compute this quantity for credit and equity exposures.
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- Blum, Jürg M., 2008. "Why 'Basel II' may need a leverage ratio restriction," Journal of Banking & Finance, Elsevier, vol. 32(8), pages 1699-1707, August.
- Jokipii, Terhi & Milne , Alistair, 2006.
"The cyclical behaviour of European bank capital buffers,"
Research Discussion Papers
17/2006, Bank of Finland.
- Jokipii, Terhi & Milne, Alistair, 2008. "The cyclical behaviour of European bank capital buffers," Journal of Banking & Finance, Elsevier, vol. 32(8), pages 1440-1451, August.
- Jokipii, Terhi & Milne, Alistair, 2007. "The Cyclical Behaviour of European Bank Capital Buffers," SIFR Research Report Series 56, Institute for Financial Research.
- Ruthenberg, David & Landskroner, Yoram, 2008. "Loan pricing under Basel II in an imperfectly competitive banking market," Journal of Banking & Finance, Elsevier, vol. 32(12), pages 2725-2733, December.
- Merton, Robert C., 1973.
"On the pricing of corporate debt: the risk structure of interest rates,"
684-73., Massachusetts Institute of Technology (MIT), Sloan School of Management.
- Merton, Robert C, 1974. "On the Pricing of Corporate Debt: The Risk Structure of Interest Rates," Journal of Finance, American Finance Association, vol. 29(2), pages 449-70, May.
- William F. Sharpe, 1964. "Capital Asset Prices: A Theory Of Market Equilibrium Under Conditions Of Risk," Journal of Finance, American Finance Association, vol. 19(3), pages 425-442, 09.
- Heid, Frank, 2007. "The cyclical effects of the Basel II capital requirements," Journal of Banking & Finance, Elsevier, vol. 31(12), pages 3885-3900, December.
- Michael B. Gordy, 2002.
"A risk-factor model foundation for ratings-based bank capital rules,"
Finance and Economics Discussion Series
2002-55, Board of Governors of the Federal Reserve System (U.S.).
- Gordy, Michael B., 2003. "A risk-factor model foundation for ratings-based bank capital rules," Journal of Financial Intermediation, Elsevier, vol. 12(3), pages 199-232, July.
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