| Table 2. Estimated stock numbers. | |||||||
| Year\Age | 2 | 3 | 4 | 5 | 6 | 7 | 8+ |
| 2005 | 16869199 | 13783737 | 7984398 | 3239728 | 1048635 | 273484 | 272393 |
| 2006 | 17734102 | 14146814 | 8186524 | 3325066 | 1085987 | 279568 | 275681 |
| 2007 | 19096202 | 15494567 | 8753814 | 3516582 | 1140526 | 300139 | 294785 |
| 2008 | 18793094 | 15401878 | 8753814 | 3492052 | 1128049 | 292436 | 290686 |
| 2009 | 18347429 | 14991591 | 8692751 | 3457305 | 1113479 | 285501 | 284930 |
| 2010 | 19638451 | 15587814 | 8939587 | 3594804 | 1154295 | 298642 | 294196 |
| 2011 | 19618823 | 16337931 | 9351058 | 3775336 | 1225672 | 315527 | 307737 |
| 2012 | 19540504 | 16223965 | 9520901 | 3836227 | 1237990 | 321901 | 319017 |
| 2013 | 19658100 | 15791778 | 9193433 | 3756507 | 1217122 | 309589 | 309279 |
| 2014 | 21552449 | 16953757 | 9568624 | 3840066 | 1236753 | 322868 | 315527 |