| Year | Count |
|---|---|
| 1987 | 5 |
| 1988 | 27 |
| 1989 | 25 |
| 1990 | 7 |
| 1991 | 8 |
| 1992 | 70 |
| 1993 | 46 |
| 1994 | 13 |
| 1996 | 26 |
| 1997 | 19 |
| 1998 | 34 |
| 1999 | 44 |
| 2000 | 43 |
| 2001 | 25 |
| 2002 | 8 |
| 2003 | 39 |
| 2004 | 29 |
| 2005 | 25 |
| 2006 | 19 |
| 2007 | 42 |
| 2008 | 168 |
| 2009 | 158 |
| 2010 | 144 |
| 2011 | 118 |
| 2012 | 150 |
| 2013 | 112 |
| 2014 | 139 |
| 2015 | 110 |
| 2016 | 101 |
| 2017 | 87 |
| 2018 | 33 |
| 2019 | 26 |
| 2020 | 26 |
| 2021 | 39 |
| 2022 | 28 |
| 2023 | 11 |
| 2024 | 28 |