E-Mini S&P

E-Mini S&P, often abbreviated to "E-mini" (despite the existence of many other E-mini contracts) and designated by the commodity ticker symbol ES, is a futures contract traded on the Chicago Mercantile Exchange's Globex electronic trading platform. The notional value of one contract is 50 times the value of the S&P 500 stock index; thus, for example, On July 11, 2016, the S&P 500 cash index closed at 2,137.16, making each E-mini contract a $106,858 bet.

The contract was introduced by the CME on September 9, 1997, after the value of the existing S&P contract (then valued at 500 times the index, or over $500,000 at the time) became too large for many small traders. The E-Mini quickly became the most popular equity index futures contract in the world. The original ("big") S&P contract was subsequently split 2:1, bringing it to 250 times the index. Hedge funds often prefer trading the E-Mini over the big S&P since the older ("big") contract still uses the open outcry pit trading method, with its inherent delays, versus the all-electronic Globex system for the E-mini. The current average daily implied volume for the E-mini is over $100 billion, far exceeding the combined traded dollar volume of the underlying 500 stocks.

Following the success of this product, the exchange introduced the E-mini NASDAQ-100 contract, at one fifth of the original NASDAQ-100 index based contract, and many other "mini" products geared primarily towards small speculators, as opposed to large hedgers.

In June 2005 the exchange introduced a yet smaller product based on the S&P, with the underlying asset being 100 shares of the highly-popular SPDR exchange-traded fund. However, due to the different regulatory requirements, the performance bond (or "margin") required for one such contract is almost as high as that for the five times larger E-Mini contract. The product never became popular, with volumes rarely exceeding 10 contracts a day.

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