| Table 3. Estimated stock numbers at age. | |||||
| Year Age | 0 | 1 | 2 | 3 | 4 |
| 2009 | 373792170 | 78719374 | 21156954 | 4205012 | 1332850 |
| 2010 | 223962548 | 63652402 | 22053663 | 5312894 | 1274748 |
| 2011 | 175618133 | 37787063 | 18023815 | 5228805 | 1301531 |
| 2012 | 205049891 | 29640199 | 9755151 | 3248392 | 880043 |
| 2013 | 371642394 | 35007526 | 8482405 | 2226244 | 723910 |
| 2014 | 428492922 | 63782711 | 10172847 | 2166199 | 563091 |
| 2015 | 308922130 | 71974545 | 17019372 | 2820614 | 716846 |
| 2016 | 311556797 | 51752181 | 15601810 | 3340631 | 578681 |
| 2017 | 311222730 | 51826517 | 9495589 | 2221209 | 471479 |