October's turnover rate came in behind January's 123, Challenger, Gray & Christmas said in a release.
October's rate of departures from the head office was 13.7 percent higher than September, when 95 CEOs left their jobs, and 18.7 percent higher than October 2011, when 91 CEOs left their jobs.
For the year to date, 999 CEOs have left their jobs, just under the 1,013 who left from January through October 2011.
Among notable exits was Citigroup CEO Vikram Pandit, whose departure was explained as a resignation, rather than a dismissal, which would have been a more accurate term to use, Challenger, Gray and Christmas said.
A second notable departure was Amini Kajunju, who was "the first African ever to serve at the helm of the oldest non-profit of its kind in the United States," her former company, the Africa-America Institute in New York, said in a statement.
Kajunju is a native of the Democratic Republic of Congo.
For October, 37 CEOs were listed as having resigned and 22 were listed as retired. An additional 14 "stepped down" and 12 took positions at other companies.
"Scandal" was listed as the reason for one departure and death was listed as the cause of another.
Eight departed because their interim positions came to an end, Challenger, Gray & Christmas said.