| Year | Count |
|---|---|
| 1980 | 7 |
| 1985 | 5 |
| 1987 | 6 |
| 1989 | 9 |
| 1990 | 12 |
| 1992 | 6 |
| 1993 | 9 |
| 1994 | 6 |
| 1995 | 13 |
| 1996 | 6 |
| 1997 | 9 |
| 1999 | 10 |
| 2000 | 18 |
| 2001 | 13 |
| 2002 | 12 |
| 2003 | 18 |
| 2004 | 8 |
| 2005 | 21 |
| 2006 | 20 |
| 2007 | 21 |
| 2008 | 29 |
| 2009 | 47 |
| 2010 | 35 |
| 2011 | 47 |
| 2012 | 29 |
| 2013 | 56 |
| 2014 | 37 |
| 2015 | 41 |
| 2016 | 92 |
| 2017 | 79 |
| 2018 | 52 |
| 2019 | 68 |
| 2020 | 62 |
| 2021 | 49 |
| 2022 | 39 |
| 2023 | 74 |
| 2024 | 77 |