| Year | Count |
|---|---|
| 1975 | 6 |
| 1988 | 15 |
| 1990 | 16 |
| 1991 | 8 |
| 1993 | 25 |
| 1994 | 29 |
| 1995 | 17 |
| 1996 | 22 |
| 1997 | 22 |
| 1998 | 39 |
| 1999 | 51 |
| 2000 | 47 |
| 2001 | 68 |
| 2002 | 52 |
| 2003 | 92 |
| 2004 | 97 |
| 2005 | 146 |
| 2006 | 132 |
| 2007 | 120 |
| 2008 | 194 |
| 2009 | 140 |
| 2010 | 158 |
| 2011 | 88 |
| 2012 | 212 |
| 2013 | 190 |
| 2014 | 203 |
| 2015 | 217 |
| 2016 | 248 |
| 2017 | 301 |
| 2018 | 502 |
| 2019 | 435 |
| 2020 | 285 |
| 2021 | 446 |
| 2022 | 362 |
| 2023 | 303 |
| 2024 | 402 |