| Year | Count |
|---|---|
| 1991 | 23 |
| 1992 | 24 |
| 1993 | 6 |
| 1994 | 19 |
| 1995 | 17 |
| 1997 | 44 |
| 1998 | 16 |
| 1999 | 52 |
| 2000 | 99 |
| 2001 | 159 |
| 2002 | 104 |
| 2003 | 108 |
| 2004 | 34 |
| 2005 | 78 |
| 2006 | 115 |
| 2007 | 97 |
| 2008 | 138 |
| 2009 | 70 |
| 2010 | 72 |
| 2011 | 48 |
| 2012 | 57 |
| 2013 | 59 |
| 2014 | 66 |
| 2015 | 70 |
| 2016 | 24 |
| 2017 | 56 |
| 2018 | 37 |
| 2019 | 20 |
| 2020 | 6 |
| 2021 | 11 |
| 2022 | 5 |
| 2023 | 5 |
| 2024 | 5 |