| Year | Count |
|---|---|
| 1987 | 29 |
| 1988 | 660 |
| 1989 | 743 |
| 1990 | 640 |
| 1991 | 886 |
| 1992 | 600 |
| 1993 | 382 |
| 1994 | 319 |
| 1995 | 261 |
| 1996 | 216 |
| 1997 | 143 |
| 1998 | 150 |
| 1999 | 96 |
| 2000 | 94 |
| 2001 | 112 |
| 2002 | 81 |
| 2003 | 49 |
| 2004 | 97 |
| 2005 | 96 |
| 2006 | 98 |
| 2007 | 83 |
| 2008 | 66 |
| 2009 | 70 |
| 2010 | 38 |
| 2011 | 52 |
| 2012 | 83 |
| 2013 | 14 |
| 2014 | 6 |
| 2015 | 29 |
| 2016 | 5 |
| 2018 | 6 |
| 2023 | 5 |