Read the following texts and table with financial data from an S&P 500 earnings report carefully.Based on the question-answer history (if provided), answer the last question. The answer may require mathematical calculation based on the data provided.


schlumberger limited and subsidiaries shares of common stock issued in treasury shares outstanding ( stated in millions ) . <table class='wikitable'><tr><td>1</td><td>-</td><td>issued</td><td>in treasury</td><td>shares outstanding</td></tr><tr><td>2</td><td>balance january 1 2008</td><td>1334</td><td>-138 ( 138 )</td><td>1196</td></tr><tr><td>3</td><td>shares sold to optionees less shares exchanged</td><td>2013</td><td>5</td><td>5</td></tr><tr><td>4</td><td>shares issued under employee stock purchase plan</td><td>2013</td><td>2</td><td>2</td></tr><tr><td>5</td><td>stock repurchase program</td><td>2013</td><td>-21 ( 21 )</td><td>-21 ( 21 )</td></tr><tr><td>6</td><td>issued on conversions of debentures</td><td>2013</td><td>12</td><td>12</td></tr><tr><td>7</td><td>balance december 31 2008</td><td>1334</td><td>-140 ( 140 )</td><td>1194</td></tr><tr><td>8</td><td>shares sold to optionees less shares exchanged</td><td>2013</td><td>4</td><td>4</td></tr><tr><td>9</td><td>vesting of restricted stock</td><td>2013</td><td>1</td><td>1</td></tr><tr><td>10</td><td>shares issued under employee stock purchase plan</td><td>2013</td><td>4</td><td>4</td></tr><tr><td>11</td><td>stock repurchase program</td><td>2013</td><td>-8 ( 8 )</td><td>-8 ( 8 )</td></tr><tr><td>12</td><td>balance december 31 2009</td><td>1334</td><td>-139 ( 139 )</td><td>1195</td></tr><tr><td>13</td><td>acquisition of smith international inc .</td><td>100</td><td>76</td><td>176</td></tr><tr><td>14</td><td>shares sold to optionees less shares exchanged</td><td>2013</td><td>6</td><td>6</td></tr><tr><td>15</td><td>shares issued under employee stock purchase plan</td><td>2013</td><td>3</td><td>3</td></tr><tr><td>16</td><td>stock repurchase program</td><td>2013</td><td>-27 ( 27 )</td><td>-27 ( 27 )</td></tr><tr><td>17</td><td>issued on conversions of debentures</td><td>2013</td><td>8</td><td>8</td></tr><tr><td>18</td><td>balance december 31 2010</td><td>1434</td><td>-73 ( 73 )</td><td>1361</td></tr></table> see the notes to consolidated financial statements part ii , item 8 .
Question: combined, what was the shares outstanding for 12/31/10 and 12/31/09?

2556.0