$EPREM Futures Premium over Cash Index

Premium of the S&P500 E-mini Futures (front month) over $SPX. This is sourced from CME and is calculated every 6 seconds.

Some feed vendors may calculate this value more frequently and it is possible for a trader with a fast and sophisticated system to calculate this themselves.

The premium is the number of points that the future is over the cash index. i.e. the difference in points between the two. This difference exists because of a concept called the cost of carry. The cost of carry implies that it costs more to hold the same basket of stocks than it does to hold the equivalent futures contract. In order for the two instruments to remain of same value the futures contract will be more expensive than the cash index.