| Year | Count |
|---|---|
| 1976 | 5 |
| 1978 | 5 |
| 1979 | 6 |
| 1981 | 8 |
| 1982 | 6 |
| 1988 | 7 |
| 1989 | 9 |
| 1990 | 6 |
| 1992 | 8 |
| 1993 | 14 |
| 1994 | 7 |
| 1995 | 11 |
| 1996 | 6 |
| 1997 | 16 |
| 1998 | 16 |
| 1999 | 16 |
| 2000 | 26 |
| 2001 | 16 |
| 2002 | 24 |
| 2003 | 19 |
| 2004 | 28 |
| 2005 | 38 |
| 2006 | 27 |
| 2007 | 29 |
| 2008 | 40 |
| 2009 | 47 |
| 2010 | 36 |
| 2011 | 21 |
| 2012 | 39 |
| 2013 | 37 |
| 2014 | 59 |
| 2015 | 74 |
| 2016 | 101 |
| 2017 | 66 |
| 2018 | 91 |
| 2019 | 99 |
| 2020 | 92 |
| 2021 | 74 |
| 2022 | 59 |
| 2023 | 71 |
| 2024 | 53 |