A computer model for comparing an index with its long-term equilibrium value is generated by analyzing historical data, including macroeconomic data, and home price index data associated with real estate properties. The model is used to generate a measure of market condition that may represent the likelihood that a real estate property is located in an overvalued or an undervalued market. The measure of market condition may, for example, be used by a mortgage lender or servicer to correct credit criteria for accepting loan requests.