| Year | Count |
|---|---|
| 1975 | 6 |
| 1978 | 5 |
| 1980 | 7 |
| 1982 | 22 |
| 1983 | 11 |
| 1984 | 14 |
| 1985 | 39 |
| 1986 | 31 |
| 1987 | 46 |
| 1988 | 30 |
| 1989 | 68 |
| 1990 | 99 |
| 1991 | 155 |
| 1992 | 161 |
| 1993 | 155 |
| 1994 | 184 |
| 1995 | 6 |
| 1995 | 277 |
| 1996 | 198 |
| 1997 | 221 |
| 1998 | 356 |
| 1999 | 442 |
| 2000 | 410 |
| 2001 | 10 |
| 2001 | 824 |
| 2002 | 6 |
| 2002 | 749 |
| 2003 | 613 |
| 2004 | 544 |
| 2005 | 424 |
| 2006 | 384 |
| 2007 | 358 |
| 2008 | 447 |
| 2009 | 392 |
| 2010 | 381 |
| 2011 | 9 |
| 2011 | 330 |
| 2012 | 301 |
| 2013 | 323 |
| 2014 | 6 |
| 2014 | 318 |
| 2015 | 328 |
| 2016 | 15 |
| 2016 | 276 |
| 2017 | 6 |
| 2017 | 136 |
| 2018 | 172 |
| 2019 | 123 |
| 2020 | 6 |
| 2020 | 166 |
| 2021 | 121 |
| 2022 | 7 |
| 2022 | 126 |
| 2023 | 7 |
| 2023 | 117 |
| 2024 | 114 |