| Year | Count |
|---|---|
| 1965 | 23 |
| 1968 | 10 |
| 1970 | 10 |
| 1971 | 14 |
| 1972 | 10 |
| 1973 | 5 |
| 1976 | 12 |
| 1981 | 10 |
| 1982 | 10 |
| 1983 | 18 |
| 1984 | 15 |
| 1985 | 35 |
| 1986 | 27 |
| 1987 | 27 |
| 1988 | 50 |
| 1989 | 84 |
| 1990 | 111 |
| 1991 | 173 |
| 1992 | 201 |
| 1993 | 49 |
| 1993 | 311 |
| 1994 | 34 |
| 1994 | 427 |
| 1995 | 10 |
| 1995 | 271 |
| 1996 | 12 |
| 1996 | 269 |
| 1997 | 282 |
| 1998 | 299 |
| 1999 | 253 |
| 2000 | 258 |
| 2001 | 317 |
| 2002 | 241 |
| 2003 | 240 |
| 2004 | 182 |
| 2005 | 192 |
| 2006 | 270 |
| 2007 | 254 |
| 2008 | 299 |
| 2009 | 174 |
| 2010 | 97 |
| 2011 | 108 |
| 2012 | 67 |
| 2013 | 77 |
| 2014 | 20 |
| 2015 | 52 |
| 2016 | 48 |
| 2017 | 51 |
| 2018 | 41 |
| 2019 | 31 |
| 2020 | 20 |
| 2021 | 40 |
| 2022 | 8 |
| 2023 | 6 |
| 2024 | 7 |