| Year | Count |
|---|---|
| 1980 | 5 |
| 1987 | 17 |
| 1988 | 7 |
| 1990 | 5 |
| 1991 | 25 |
| 1992 | 41 |
| 1993 | 23 |
| 1994 | 34 |
| 1995 | 36 |
| 1996 | 42 |
| 1997 | 35 |
| 1998 | 46 |
| 1999 | 64 |
| 2000 | 56 |
| 2001 | 71 |
| 2002 | 74 |
| 2003 | 65 |
| 2004 | 70 |
| 2005 | 54 |
| 2006 | 71 |
| 2007 | 56 |
| 2008 | 5 |
| 2008 | 44 |
| 2009 | 58 |
| 2010 | 51 |
| 2011 | 44 |
| 2012 | 51 |
| 2013 | 23 |
| 2014 | 35 |
| 2015 | 36 |
| 2016 | 30 |
| 2017 | 19 |
| 2018 | 18 |
| 2019 | 26 |
| 2020 | 27 |
| 2021 | 12 |
| 2022 | 27 |
| 2023 | 30 |
| 2024 | 22 |