| Year | Count |
|---|---|
| 1989 | 7 |
| 1992 | 9 |
| 1993 | 8 |
| 1994 | 6 |
| 1995 | 12 |
| 1996 | 44 |
| 1997 | 34 |
| 1998 | 58 |
| 1999 | 42 |
| 2000 | 56 |
| 2001 | 94 |
| 2002 | 109 |
| 2003 | 112 |
| 2004 | 246 |
| 2005 | 228 |
| 2006 | 286 |
| 2007 | 394 |
| 2008 | 351 |
| 2009 | 426 |
| 2010 | 420 |
| 2011 | 470 |
| 2012 | 533 |
| 2013 | 488 |
| 2014 | 478 |
| 2015 | 627 |
| 2016 | 601 |
| 2017 | 602 |
| 2018 | 364 |
| 2019 | 468 |
| 2020 | 424 |
| 2021 | 489 |
| 2022 | 430 |
| 2023 | 420 |
| 2024 | 396 |