| Year | Count |
|---|---|
| 1986 | 13 |
| 1987 | 23 |
| 1988 | 20 |
| 1989 | 26 |
| 1990 | 18 |
| 1991 | 23 |
| 1992 | 69 |
| 1993 | 43 |
| 1994 | 27 |
| 1995 | 20 |
| 1996 | 32 |
| 1997 | 20 |
| 1998 | 17 |
| 1999 | 57 |
| 2000 | 38 |
| 2001 | 38 |
| 2002 | 45 |
| 2003 | 10 |
| 2004 | 9 |
| 2005 | 28 |
| 2006 | 28 |
| 2007 | 8 |
| 2008 | 45 |
| 2009 | 22 |
| 2010 | 5 |
| 2011 | 15 |
| 2013 | 35 |
| 2014 | 10 |
| 2015 | 12 |
| 2016 | 8 |
| 2019 | 5 |