| Year | Count |
|---|---|
| 1974 | 5 |
| 1975 | 5 |
| 1977 | 12 |
| 1979 | 44 |
| 1980 | 47 |
| 1981 | 75 |
| 1982 | 67 |
| 1983 | 33 |
| 1984 | 106 |
| 1985 | 82 |
| 1986 | 155 |
| 1987 | 148 |
| 1988 | 165 |
| 1989 | 188 |
| 1990 | 289 |
| 1991 | 374 |
| 1992 | 235 |
| 1993 | 212 |
| 1994 | 291 |
| 1995 | 175 |
| 1996 | 231 |
| 1997 | 275 |
| 1998 | 291 |
| 1999 | 244 |
| 2000 | 250 |
| 2001 | 289 |
| 2002 | 256 |
| 2003 | 373 |
| 2004 | 568 |
| 2005 | 507 |
| 2006 | 426 |
| 2007 | 515 |
| 2008 | 461 |
| 2009 | 438 |
| 2010 | 429 |
| 2011 | 380 |
| 2012 | 377 |
| 2013 | 322 |
| 2014 | 258 |
| 2015 | 372 |
| 2016 | 313 |
| 2017 | 322 |
| 2018 | 178 |
| 2019 | 155 |
| 2020 | 108 |
| 2021 | 153 |
| 2022 | 186 |
| 2023 | 100 |
| 2024 | 90 |