| Year | Count |
|---|---|
| 1976 | 10 |
| 1977 | 16 |
| 1978 | 14 |
| 1978 | 9 |
| 1981 | 8 |
| 1981 | 5 |
| 1983 | 15 |
| 1984 | 17 |
| 1985 | 5 |
| 1985 | 20 |
| 1986 | 5 |
| 1986 | 14 |
| 1987 | 20 |
| 1988 | 5 |
| 1988 | 30 |
| 1989 | 23 |
| 1990 | 6 |
| 1990 | 50 |
| 1991 | 71 |
| 1992 | 5 |
| 1992 | 104 |
| 1993 | 20 |
| 1993 | 132 |
| 1994 | 10 |
| 1994 | 293 |
| 1995 | 10 |
| 1995 | 184 |
| 1996 | 123 |
| 1997 | 174 |
| 1998 | 127 |
| 1999 | 71 |
| 2000 | 90 |
| 2001 | 55 |
| 2002 | 23 |
| 2003 | 17 |
| 2004 | 6 |
| 2005 | 12 |
| 2006 | 6 |
| 2007 | 12 |
| 2008 | 11 |
| 2010 | 5 |
| 2011 | 5 |
| 2012 | 5 |
| 2013 | 10 |
| 2014 | 7 |
| 2017 | 10 |
| 2019 | 7 |
| 2022 | 6 |