Income Tax
Prior to our initial public offering, we were a limited liability company and were not subject to federal or state income taxes. Actual income tax expense represents income taxes incurred from July 13, 1998, the date of the reorganization, through December 31, 1998 and for the year ended December 31, 1999. This period is referred to as the post-offering period. Our effective tax rate for the post-offering period and pro forma effective tax rate for all periods prior to the post-offering period differ from the federal statutory rate of 35% due to state income taxes, as well as nondeductible expenses, including the amortization of goodwill resulting from the acquisition of Trimark and a portion of business development expenses and merger-related expenses.

Results of Operations
The following table sets forth the consolidated statement of income data as a percentage of total revenues: