Pre-market data on stock market futures are available on financial websites such as CNNMoney.com and CNBC.com. These data provide an indication of the direction the stock market is heading, says Zacks Investment Research.
The Chicago Mercantile Exchange offers trading of stock market futures, as stated by Zacks Investment Research. Investors who trade these futures predict the value of stock market indexes, such as the Nasdaq stock index and the Standard & Poor's 500 stock index, on the expiration dates of these futures in March, June, September and December, according to Zacks Investment Research. The expiration date normally falls on the third Friday of these months, says Investopedia.