| Year | Count |
|---|---|
| 1986 | 8 |
| 1989 | 11 |
| 1991 | 7 |
| 1992 | 15 |
| 1995 | 16 |
| 1996 | 19 |
| 1997 | 21 |
| 1998 | 40 |
| 1999 | 120 |
| 2000 | 57 |
| 2001 | 100 |
| 2002 | 102 |
| 2003 | 177 |
| 2004 | 169 |
| 2005 | 241 |
| 2006 | 203 |
| 2007 | 267 |
| 2008 | 344 |
| 2009 | 235 |
| 2010 | 223 |
| 2011 | 134 |
| 2012 | 155 |
| 2013 | 185 |
| 2014 | 134 |
| 2015 | 134 |
| 2016 | 136 |
| 2017 | 141 |
| 2018 | 102 |
| 2019 | 71 |
| 2020 | 47 |
| 2021 | 26 |
| 2022 | 38 |
| 2023 | 45 |
| 2024 | 16 |