CNBC pre-market futures indicate how major market indexes open or close on any given trading day, according to Investopedia. Professional investors buy and sell stocks before the major market indexes open for regular trading, and those pre-market trades affect how financial indexes perform for the day.
CNBC lists futures for the Dow Jones Industrial Average, the S&P 500, the NASDAQ and the Russell 2000. Each future value shows the index's previous day’s close and the current future value of the index before each market opens for the day’s trading. Pre-market futures help investors determine whether major market indexes open higher or lower than the previous day’s trading, explains Investopedia.