| Year | Count |
|---|---|
| 1974 | 8 |
| 1976 | 10 |
| 1977 | 10 |
| 1979 | 21 |
| 1980 | 10 |
| 1981 | 5 |
| 1982 | 10 |
| 1983 | 23 |
| 1984 | 14 |
| 1985 | 50 |
| 1986 | 52 |
| 1987 | 64 |
| 1988 | 117 |
| 1989 | 104 |
| 1990 | 215 |
| 1991 | 538 |
| 1992 | 525 |
| 1993 | 535 |
| 1994 | 515 |
| 1995 | 495 |
| 1996 | 502 |
| 1997 | 544 |
| 1998 | 488 |
| 1999 | 352 |
| 2000 | 335 |
| 2001 | 294 |
| 2002 | 204 |
| 2003 | 288 |
| 2004 | 343 |
| 2005 | 334 |
| 2006 | 329 |
| 2007 | 353 |
| 2008 | 402 |
| 2009 | 375 |
| 2010 | 358 |
| 2011 | 379 |
| 2012 | 340 |
| 2013 | 266 |
| 2014 | 253 |
| 2015 | 304 |
| 2016 | 328 |
| 2017 | 283 |
| 2018 | 181 |
| 2019 | 167 |
| 2020 | 166 |
| 2021 | 132 |
| 2022 | 143 |
| 2023 | 250 |
| 2024 | 171 |