ADTRAN, INC. Consolidated Statements of Changes in Stockholders’ Equity  Years ended December 31, 2013, 2012 and 2011  (In thousands) Common  Shares Common  Stock Additional  Paid-In  Capital Retained Earnings Treasury Stock Accumulated Other Comprehensive Income Total Stockholders’ Equity Balance, December 31, 2010 79,652 $797 $193,866 $731,962 $(381,251) $26,948 $572,322 Net income 138,577 138,577 Other comprehensive loss, net of tax (13,846) (13,846) Dividend payments (23,124) (23,124) Dividends accrued for unvested restricted stock units (52) (52) Stock options exercised (6,345) 40,470 34,125 Restricted stock units vested (812) 812 — Purchase of treasury stock: 1,112 shares (35,565) (35,565) Income tax benefit from exercise of stock options 10,525 10,525 Stock-based compensation expense 9,169 9,169 Balance, December 31, 2011 79,652 $797 $213,560 $840,206 $(375,534) $13,102 $692,131 Net income 47,263 47,263 Other comprehensive loss, net of tax (1,834) (1,834) Dividend payments (22,813) (22,813) Dividends accrued for unvested restricted stock units 15 15 Stock options exercised (2,659) 8,708 6,049 Restricted stock units vested (212) (547) 547 (212) Purchase of treasury stock: 1,786 shares (39,362) (39,362) Income tax benefit from exercise of stock options 1,905 1,905 Stock-based compensation expense 9,264 9,264 Balance, December 31, 2012 79,652 $797 $224,517 $861,465 $(405,641) $11,268 $692,406 Net income 45,794 45,794 Other comprehensive loss, net of tax (515) (515) Dividend payments (21,412) (21,412) Dividends accrued for unvested restricted stock units (23) (23) Stock options exercised (762) 4,391 3,629 Restricted stock units vested (248) (611) 611 (248) Purchase of treasury stock: 5,608 shares (124,267) (124,267) Income tax benefit from exercise of stock options 169 169 Stock-based compensation expense 9,073 9,073 Balance, December 31, 2013 79,652 $797 $233,511 $884,451 $(524,906) $10,753 $604,606 We issued 217 shares, 393 shares and 1,813 shares of treasury stock to accommodate employee stock option exercises, vesting of restricted stock, and vesting of restricted stock units during 2013, 2012 and 2011, respectively. During 2011, we  received 7 shares, previously held by employees for at least six months as payment of the exercise price for employee stock options. None of the transactions with respect to these shares were made in the open market. The average price paid per share with respect to these transactions was based on the closing price of the common stock on the NASDAQ Global Select Market on the date of the transaction. There were no such transactions during 2012 and 2013. See notes to consolidated financial statements.  ADTRAN 2013 Annual Report 38