| Year | Count |
|---|---|
| 1987 | 10 |
| 1988 | 6 |
| 1989 | 6 |
| 1990 | 6 |
| 1991 | 6 |
| 1995 | 8 |
| 1996 | 24 |
| 1997 | 26 |
| 1998 | 19 |
| 1999 | 59 |
| 2000 | 52 |
| 2001 | 51 |
| 2002 | 83 |
| 2003 | 56 |
| 2004 | 100 |
| 2005 | 115 |
| 2006 | 162 |
| 2007 | 192 |
| 2008 | 192 |
| 2009 | 222 |
| 2010 | 349 |
| 2011 | 369 |
| 2012 | 704 |
| 2013 | 682 |
| 2014 | 710 |
| 2015 | 783 |
| 2016 | 793 |
| 2017 | 555 |
| 2018 | 732 |
| 2019 | 650 |
| 2020 | 470 |
| 2021 | 576 |
| 2022 | 473 |
| 2023 | 401 |
| 2024 | 375 |