Total operating revenues for the fourth quarter of 2011 rose 2% to $120.2m, compared to $117.4m for the same period a year ago.

The increase in operating revenues reflects a $7.2m increase in transaction fees and a $0.7m increase in exchange services and other fees, offset by a $1.3m decrease in access fees.

Operating income was $52.7m, compared to $51.9m for the same period in the previous year.

The company’s operating margin decreased to 43.8%, compared to 44.2% for the same period in the last year.

CBOE Holdings executive vice president and CFO Alan Dean said that their strong cash flow enabled us to return nearly $92m to stockholders through dividends and share repurchases, bringing the total returned to stockholders over the past 18 months to more than $525m.