SEI Investments Company (SEIC)

Earnings per Share

The calculations of basic and diluted earnings per share for the three months ended March 31, 2009 and 2008 are:

Employee stock options to purchase 26,078,000 and 6,017,000 shares of common stock, with an average exercise price of $20.51 and $30.83, were outstanding during the three month periods ended March 31, 2009 and 2008, respectively, but not included in the computation of diluted earnings per common share because the effect on diluted earnings per common share would have been anti-dilutive.

Page 8 of 42

Earnings per Share

The calculations of basic and diluted earnings per share for the three months ended March 31, 2008 and 2007 are:

Employee stock options to purchase 6,017,000 and 3,612,000 shares of common stock, with an average exercise price of $30.83 and $29.52, were outstanding during the three month periods ended March 31, 2008 and 2007, respectively, but not included in the computation of diluted earnings per common share because the effect on diluted earnings per common share would have been anti-dilutive.

Earnings per Share

The Company calculates earnings per common share in accordance with Statement of Financial Accounting Standards No. 128, “Earnings per Share.” Basic earnings per common share is computed by dividing net income available to common shareholders by the weighted average number of common shares outstanding for the period. Diluted earnings per common share is computed by dividing net income available to common shareholders by the combination of the weighted average number of common shares outstanding and the dilutive potential common shares, such as stock options, outstanding during the period. The calculations of basic and diluted earnings per share for the three months ended March 31, 2007 and 2006 are:

Employee stock options to purchase 1,806,000 and 6,705,000 shares of common stock, with an average exercise price of $59.04 and $42.56, were outstanding during the three month periods ended March 31, 2007 and 2006, respectively, but not included in the computation of diluted earnings per common share because the effect on diluted earnings per common share would have been anti-dilutive.

Earnings per Share

The Company calculates earnings per common share in accordance with Statement of Financial Accounting Standards No. 128, “Earnings per Share.” Basic earnings per common share is computed by dividing net income available to common shareholders by the weighted average number of common shares outstanding for the period. Diluted earnings per common share is computed by dividing net income available to common shareholders by the combination of the weighted average number of common shares outstanding and the dilutive potential common shares, such as stock options, outstanding during the period. The calculations of basic and diluted earnings per share for the three months ended March 31, 2006 and 2005 are:

Employee stock options to purchase 6,705,000 and 4,663,000 shares of common stock, with an average exercise price of $42.56 and $44.54, were outstanding during the three month periods ended March 31, 2006 and 2005, respectively, but not included in the computation of diluted earnings per common share because the effect on diluted earnings per common share would have been anti-dilutive.

Page 10

Earnings per Share

The Company calculates earnings per common share in accordance with Statement of Financial Accounting Standards No. 128, “Earnings per Share.” Basic earnings per common share is computed by dividing net income available to common shareholders by the weighted average number of common shares outstanding for the period. Diluted earnings per common share is computed by dividing net income available to common shareholders by the combination of the weighted average number of common shares outstanding and the dilutive potential common shares, such as stock options, outstanding during the period. The calculations of basic and diluted earnings per share for the three months ended March 31, 2005 and 2004 are:

Employee stock options to purchase 4,663,000 and 2,619,000 shares of common stock, with an average exercise price of $44.54 and $45.55, were outstanding during the three month periods ended March 31, 2005 and 2004, respectively, but not included in the computation of diluted earnings per common share because the exercise price of the options was greater than the average market price of the Company’s common stock, and the effect on diluted earnings per common share would have been anti-dilutive.