Trading volume at CME Group Inc. (CME) fell 23% in April compared to the same time a year ago, even as the world's largest futures exchange reported increased activity in its most popular stock index product.

An average 9.2 million contracts were traded each day in April, said CME - which operates the Chicago Mercantile Exchange, Chicago Board of Trade, and the energy-dominated New York Mercantile Exchange.

Meantime, one of CME's primary competitors, IntercontinentalExchange Inc. (ICE), said Monday that average daily volume in its futures complex climbed 14% in April, with almost 984,000 contracts changing hands on a daily basis.

CME shares were recently priced at $229.29, up 3%. Shares of ICE were valued at $88.35, up 3.7%. Both companies benefited Monday from a broad-based stock market rally.

The daily average for ICE edged up slightly in Europe during April, while the figure jumped 42% in the U.S. on an increase in some sugar options and futures, and a huge jump in ICE's Russell 2000 mini stock index product.

The exchange said almost 152,000 Russell 2000 contracts changed hands in April, compared to only about 1,675 contracts the same time last year.

Last September, ICE became the exclusive venue for Russell products.

The Atlanta-based firm is primarily energy-focused, but is attempting to attract business to its first-in-the-U.S. clearing house for over-the-counter credit derivatives.

Launched in early March, the exchange said ICE US Trust has cleared 2,493 over-the-counter credit default swaps, with a notional value of $257 billion.

A month ago, ICE said it had cleared $45 billion in credit default swap transactions.

One of the few silver linings for CME was the performance of its electronically-traded E-mini stock index complex. It rose 18% from April, 2008, with an average 2.9 million contracts per day.

Market participants attributed the increased business in e-mini equities to the stock market's rebound of recent weeks, which in turn lured back investors who had been on the sidelines.

The stock market rally failed to produce increases in CME's core interest rate product group. Trading plunged 45% in April, versus the same time last year, with average daily volume of 3.3 million contracts.

Average daily volume for CME's most heavily traded interest rate product, Eurodollar futures and options, fell 47% in April, trading 1.9 million contracts.

Eurodollar futures are tied to market expectations for movement in the key London Interbank Offered Rate.

Since the onset of the credit crunch, the spread separating the three-month dollar Libor and the U.S. federal-funds rate has been unusually wide. As a result, many traders have stopped using Eurodollar futures to measure U.S. funds rate expectations.

CME said volume for fed-funds futures and options were down 64% in April compared to the year-ago period, with an average of about 50,000 contracts traded daily.

Treasury futures and options activity dropped 42%, compared to April 2008, with average daily volume last month at about 1.3 million contracts. The April decline came even as the U.S. Treasury issues record amounts of cash securities to pay off government debt.

Increases in cash Treasury sales presumably offer futures participants opportunities to hedge their cash market positions.

Another bright spot for CME was the performance of its Clearport system, which provides clearing services for over-the-counter traders. Clearport processed a daily average of 533,000 a day in April, up 24%.

Average daily volume for commodities and alternative investments, like weather derivatives, were down 15% from the year ago period, but 28% higher versus March, according to CME.

Volume was down 26% in April for the foreign exchange complex, once considered a high-growth area at CME.

The exchange also said volume for Nymex energy and metals was 9% lower in April, averaging 1.6 million contracts per day.

CME shares were recently priced at $229.60, up 3.1%. Shares of ICE were valued at $88.25, up 3.6%. Both companies benefited Monday from a broad-based stock market rally.

-By Howard Packowitz, Dow Jones Newswires; 312-750-4132; howard.packowitz@dowjones.com and Kerry E. Grace, Dow Jones Newswires; 201-938-5089; kerry.grace@dowjones.com