Three Months Ended  (dollars in thousands, except per share amounts) Mar. 31, Jun. 30, Sep. 30, Dec. 31, Mar. 31, Jun. 30, Sep. 30, Dec. 31, 1999 1999 1999 1999 2000 2000 2000 2000 Core research $12,978 $14,773 $17,026 $19,919 $23,759 $28,011 $32,270 $36,438 Advisory services  and other 4,951 4,898 4,955 7,768 7,058 10,269 7,867 11,476 Total revenues 17,929 19,671 21,981 27,687 30,817 38,280 40,137 47,914 Cost of services  and fulfillment 6,612 6,424 6,909 7,770 9,295 11,674 11,294 13,208 Selling and marketing 6,192 7,276 7,854 9,809 12,214 14,323 14,785 16,635 General and  administrative 2,041 2,213 2,504 3,107 3,780 4,703 4,729 5,420 Depreciation and  amortization 873 1,048 973 1,109 1,432 1,750 1,984 2,778 Costs related  to acquisition — — — 694 — — — — Income from  operations 2,211 2,710 3,741 5,198 4,096 5,830 7,345 9,873 Other income, net 860 895 864 1,092 1,454 1,972 2,157 1,310 Income before income  tax provision 3,071 3,605 4,605 6,290 5,550 7,802 9,502 11,183 Income tax provision 1,167 1,370 1,750 2,302 2,081 2,926 3,563 3,853 Net income $1,904 $2,235 $2,855 $3,988 $3,469 $4,876 $5,939 $7,330 Basic net income per  common share $0.11 $0.13 $0.16 $0.21 $0.17 $0.23 $0.28 $0.34 Diluted net income  per common share $0.10 $0.12 $0.14 $0.18 $0.15 $0.20 $0.24 $0.30 As a Percentage of Revenues Mar. 31, Jun. 30, Sep. 30, Dec. 31, Mar. 31, Jun. 30, Sep. 30, Dec. 31, 1999 1999 1999 1999 2000 2000 2000 2000 Core research 72% 75% 77% 74% 77% 73% 80% 76% Advisory services  and other 28 25 23 26 23 27 20 24 Total revenues 100 100 100 100 100 100 100 100 Cost of services and  fulfillment 37 33 31 28 30 31 28 29 Selling and marketing 35 37 36 35 40 37 37 37 General and  administrative 11 11 11 11 12 12 12 12 Depreciation and  amortization 5 5 5 4 5 5 5 5 Costs related  to acquisition — — — 3 — — — — Income from  operations 12 14 17 19 13 15 18 17 Other income, net 5 4 4 4 5 5 6 5 Income before income  tax provision 17 18 21 23 18 20 24 22 Income tax provision 6 7 8 9 7 7 9 8 Net income 11% 11% 13% 14% 11% 13% 15% 14%