12 Summarized Quarterly Financial Data (Unaudited) Unaudited Quarterly Operating Results  35 Financial Results The following table presents unaudited quarterly operating results for each of ADTRAN’s last eight fiscal quarters. This information has been prepared by ADTRAN on a basis consistent with our audited financial statements and includes all adjustments, consisting only of normal recurring adjustments, considered necessary for a fair presentation of the data. (In thousands, except for per share amounts) (1) Net income for the three months ended June 30, 2002, and September 30, 2002, includes other-than-temporary  investment impairment charges, resulting in an after-tax loss of $853,992 and $6,576,573, respectively. (2) Assumes exercise of dilutive stock options calculated under the treasury stock method. Three months ended March 31, 2002 June 30, 2002 September 30, 2002 December 31, 2002 Net sales $83,342 $85,784 $88,180 $88,419 Gross profit $39,359 $41,623 $45,525 $48,429 Operating income $4,735 $6,710 $11,930 $14,150 Net income (1) $4,341 $4,967 $3,358 $12,110 Earnings per common share $_{*}$ assuming dilution (2) $0.11 $0.13 $0.09 $0.32 Earnings per common share $0.11 $0.13 $0.09 $0.32 Three months ended March 31, 2001 June 30, 2001 September 30, 2001 December 31, 2001 Net sales $105,276 $97,198 $95,513 $89,094 Gross profit $45,434 $45,559 $42,399 $39,929 Operating income $4,521 $5,796 $5,098 $3,017 Net income $3,959 $4,637 $4,950 $3,783 Earnings per common share  assuming dilution (2) $0.10 $0.12 $0.13 $0.10 Earnings per common share $0.10 $0.12 $0.13 $0.10