| Year | Count |
|---|---|
| 1983 | 6 |
| 1986 | 7 |
| 1987 | 8 |
| 1988 | 5 |
| 1991 | 9 |
| 1992 | 7 |
| 1993 | 7 |
| 1994 | 11 |
| 1995 | 8 |
| 1997 | 7 |
| 1998 | 9 |
| 1999 | 16 |
| 2000 | 16 |
| 2001 | 17 |
| 2002 | 15 |
| 2003 | 28 |
| 2004 | 15 |
| 2005 | 37 |
| 2006 | 45 |
| 2007 | 43 |
| 2008 | 41 |
| 2009 | 37 |
| 2010 | 44 |
| 2011 | 52 |
| 2012 | 48 |
| 2013 | 73 |
| 2014 | 88 |
| 2015 | 90 |
| 2016 | 258 |
| 2017 | 321 |
| 2018 | 270 |
| 2019 | 212 |
| 2020 | 184 |
| 2021 | 190 |
| 2022 | 204 |
| 2023 | 168 |
| 2024 | 162 |