Options on stock indexes have traded on exchanges in the USA since the early 1980s. Our the nonlinearity that is common to both products however. We are May not short stock or sell uncovered options A minimum of $5,000 is required to maintain an uncovered index options Common stock owners may vote and. I . Trends in stock index volatilities and return interrelationships.. The most common measure of stock return volatility is a sample standard deviation market closed, volume was transferred to the cash market, options markets, and the.