A method and system for generating a real estate property index uses real estate data including price data, property data and time of sale data that are entered into a computing apparatus. The time of sale data is manipulated to provide consecutive triple times giving two consecutive time periods (e.g., March, April, May 2007 and April, May, June 2007). A transform function, preferably a log function, is generated with two time dummy variables, and the coefficients of the two time dummy variables are extracted and added to generate a transformed growth rate. The reverse transform function, preferably an anti-log function, is generated to provide the desired untransformed growth rate.