what was the net change in shares outstanding during 2011?
schlumberger limited and subsidiaries shares of common stock ( stated in millions ) issued in treasury shares outstanding .

|  | Issued | In Treasury | Shares Outstanding |
| :--- | :--- | :--- | :--- |
| Balance, January 1, 2009 | 1,334 | (140) | 1,194 |
| Shares sold to optionees less shares exchanged | – | 4 | 4 |
| Vesting of restricted stock | – | 1 | 1 |
| Shares issued under employee stock purchase plan | – | 4 | 4 |
| Stock repurchase program | – | (8) | (8) |
| Balance, December 31, 2009 | 1,334 | (139) | 1,195 |
| Acquisition of Smith International, Inc. | 100 | 76 | 176 |
| Shares sold to optionees less shares exchanged | – | 6 | 6 |
| Shares issued under employee stock purchase plan | – | 3 | 3 |
| Stock repurchase program | – | (27) | (27) |
| Issued on conversions of debentures | – | 8 | 8 |
| Balance, December 31, 2010 | 1,434 | (73) | 1,361 |
| Shares sold to optionees less shares exchanged | – | 6 | 6 |
| Vesting of restricted stock | – | 1 | 1 |
| Shares issued under employee stock purchase plan | – | 3 | 3 |
| Stock repurchase program | – | (37) | (37) |
| Balance, December 31, 2011 | 1,434 | (100) | 1,334 |

see the notes to consolidated financial statements .

shares_change = 1434 - 1434
answer = shares_change