<Li> 1989 - Brenner and Galai's paper is published in Financial Analysts Journal . Brenner and Galai develop their research further in graduate symposia at The Hebrew University of Jerusalem and the Leonard M. Stern School of Business at New York University . </Li> <Li> 1992 - The American Stock Exchange announced it is conducting a feasibility study on a volatility index, proposed as the "Sigma Index ." "SI would be an underlying asset for futures and options that investors would use to hedge against the risk of volatility changes in the stock market ." </Li> <Li> 1993 - On January 19, 1993, the Chicago Board Options Exchange held a press conference to announce the launch of real - time reporting of the CBOE Market Volatility Index or VIX . The formula that determines the VIX is tailored to the CBOE S&P 100 Index (OEX) option prices, and was developed by Robert Whaley . </Li> <Li> 2003 - The CBOE introduced a more detailed methodology for the VIX . Working with Goldman Sachs, the CBOE developed further computational methodologies, and changed the underlying index the CBOE S&P 100 Index (OEX) to the CBOE S&P 500 Index (SPX). </Li>

What is the volatility of the s&p 500