| Year | Count |
|---|---|
| 1981 | 5 |
| 1983 | 6 |
| 1988 | 6 |
| 1989 | 5 |
| 1990 | 5 |
| 1991 | 10 |
| 1992 | 5 |
| 1993 | 15 |
| 1994 | 60 |
| 1995 | 72 |
| 1996 | 49 |
| 1997 | 101 |
| 1998 | 89 |
| 1999 | 75 |
| 2000 | 78 |
| 2001 | 115 |
| 2002 | 117 |
| 2003 | 82 |
| 2004 | 75 |
| 2005 | 76 |
| 2006 | 62 |
| 2007 | 87 |
| 2008 | 90 |
| 2009 | 91 |
| 2010 | 124 |
| 2011 | 135 |
| 2012 | 91 |
| 2013 | 98 |
| 2014 | 109 |
| 2015 | 94 |
| 2016 | 315 |
| 2017 | 309 |
| 2018 | 294 |
| 2019 | 154 |
| 2020 | 146 |
| 2021 | 150 |
| 2022 | 120 |
| 2023 | 144 |
| 2024 | 140 |