Chicago Mercantile Exchange ( CME) said Chief Financial Officer David G. Gomach would depart this fall to spend more time with his family.The company said Gomach will help the exchange identify a replacement. The CME hired Russell Reynolds Associates to lead a search that will consider both internal and external candidates. "CME has made a successful transition to public company status and is successfully executing its growth strategy," said Gomach. "Now, as CME has achieved an enviable competitive position as the largest futures exchange and first publicly traded exchange in the U.S., I believe I have accomplished my goals and I can focus my energies on helping CME find my successor." The Chicago-based company said Gomach, who joined the company in 1987, will depart in November. Gomach's family relocated to Wisconsin last year. On Wednesday, CME shares slipped $2.67 to $131.13.