| Year | Count |
|---|---|
| 1988 | 5 |
| 1991 | 5 |
| 1992 | 8 |
| 1993 | 7 |
| 1994 | 9 |
| 1995 | 17 |
| 1996 | 34 |
| 1997 | 38 |
| 1998 | 20 |
| 1999 | 34 |
| 2000 | 45 |
| 2001 | 51 |
| 2002 | 52 |
| 2003 | 57 |
| 2004 | 51 |
| 2005 | 55 |
| 2006 | 50 |
| 2007 | 57 |
| 2008 | 55 |
| 2009 | 51 |
| 2010 | 48 |
| 2011 | 58 |
| 2012 | 74 |
| 2013 | 64 |
| 2014 | 60 |
| 2015 | 87 |
| 2016 | 150 |
| 2017 | 165 |
| 2018 | 204 |
| 2019 | 164 |
| 2020 | 146 |
| 2021 | 122 |
| 2022 | 118 |
| 2023 | 112 |
| 2024 | 94 |