CME S&P 500 Open Interest Surges Past 550,000 For First Time - E-mini S&P 500 And MidCap 400 Continue To Set Open Interest Records

For the eighth consecutive session, open interest in S&P 500 Index futures traded on Chicago Mercantile Exchange Inc. (CME) has continued to surge, reaching a record 563,141 positions at the close of trading on Wednesday. The new record surpasses the previous day's record of 546,909 positions culminating in a 14 percent increase in open interest since Dec. 4 when 494,331 positions were open at the close of trading.

Also on Wednesday and for the second consecutive session, open interest in E-mini S&P 500 futures rose to a new high of 85,145 positions compared to the previous day's record of 83,163. On Dec. 11, the S&P MidCap 400 began a record-setting week with 21,138 in open interest, reaching a record 21,333 on Dec. 13.

Open interest is the number of contracts outstanding at the close of the trading day. High open interest in a product is an indication-in conjunction with its trading volume-of its "liquidity."