| Year | Count |
|---|---|
| 1988 | 10 |
| 1989 | 16 |
| 1990 | 73 |
| 1991 | 49 |
| 1992 | 102 |
| 1993 | 133 |
| 1994 | 166 |
| 1995 | 406 |
| 1996 | 570 |
| 1997 | 770 |
| 1998 | 804 |
| 1999 | 669 |
| 2000 | 692 |
| 2001 | 648 |
| 2002 | 501 |
| 2003 | 476 |
| 2004 | 575 |
| 2005 | 557 |
| 2006 | 564 |
| 2007 | 818 |
| 2008 | 740 |
| 2009 | 610 |
| 2010 | 597 |
| 2011 | 632 |
| 2012 | 706 |
| 2013 | 612 |
| 2014 | 604 |
| 2015 | 703 |
| 2016 | 558 |
| 2017 | 615 |
| 2018 | 500 |
| 2019 | 445 |
| 2020 | 338 |
| 2021 | 361 |
| 2022 | 344 |
| 2023 | 311 |
| 2024 | 271 |