| Table 3. Estimated stock numbers at age. | |||||
| Year Age | 0 | 1 | 2 | 3 | 4 | 
| 1997 | 163091205 | 26134849 | 8703592 | 1247253 | 63869 | 
| 1998 | 191275303 | 27685123 | 7964441 | 2364042 | 117169 | 
| 1999 | 389843424 | 32362450 | 8315254 | 1952408 | 175926 | 
| 2000 | 382125761 | 67064683 | 9529676 | 1958892 | 161506 | 
| 2001 | 339314626 | 65586666 | 20306335 | 2325062 | 190364 | 
| 2002 | 216084832 | 58009463 | 19589690 | 5526861 | 337749 | 
| 2003 | 210409220 | 36538328 | 16980771 | 5068548 | 886937 | 
| 2004 | 182417657 | 35532532 | 9958494 | 3777076 | 487630 | 
| 2005 | 222952958 | 30856473 | 9686490 | 2275721 | 474816 | 
| 2006 | 299749962 | 37927392 | 7889927 | 1610348 | 173033 | 
| 2007 | 473870547 | 50637635 | 10557066 | 1999208 | 283891 | 
| 2008 | 501024680 | 80363684 | 14909614 | 3533810 | 576183 | 
| 2009 | 420122487 | 85566038 | 23934458 | 4914486 | 1206288 | 
| 2010 | 206926628 | 71743766 | 24614559 | 6742964 | 1543025 | 
| 2011 | 171967958 | 34690394 | 19866762 | 5814074 | 1631071 | 
| 2012 | 262279479 | 28806879 | 8445315 | 2788963 | 829923 | 
| 2013 | 378535163 | 45009320 | 7779148 | 1788393 | 604666 | 
| 2014 | 400933454 | 64947428 | 12610141 | 1914127 | 401707 | 
| 2015 | 316610325 | 67426304 | 18370032 | 4256023 | 766688 | 
| 2016 | 349002683 | 53016009 | 15007238 | 3440173 | 654115 | 
| 2017 | 338542320 | 58471078 | 11167843 | 2498921 | 446188 |