| Year | Count |
|---|---|
| 1977 | 7 |
| 1978 | 5 |
| 1981 | 5 |
| 1989 | 5 |
| 1990 | 7 |
| 1992 | 10 |
| 1993 | 9 |
| 1996 | 6 |
| 1997 | 7 |
| 1998 | 7 |
| 1999 | 31 |
| 2000 | 24 |
| 2001 | 37 |
| 2002 | 33 |
| 2003 | 41 |
| 2004 | 75 |
| 2005 | 82 |
| 2006 | 109 |
| 2007 | 107 |
| 2008 | 116 |
| 2009 | 99 |
| 2010 | 96 |
| 2011 | 102 |
| 2012 | 136 |
| 2013 | 143 |
| 2014 | 138 |
| 2015 | 87 |
| 2016 | 176 |
| 2017 | 282 |
| 2018 | 191 |
| 2019 | 193 |
| 2020 | 130 |
| 2021 | 241 |
| 2022 | 214 |
| 2023 | 172 |
| 2024 | 147 |