| Year | Count |
|---|---|
| 1982 | 6 |
| 1983 | 5 |
| 1984 | 15 |
| 1985 | 11 |
| 1986 | 39 |
| 1987 | 39 |
| 1988 | 75 |
| 1989 | 104 |
| 1990 | 187 |
| 1991 | 232 |
| 1992 | 322 |
| 1993 | 292 |
| 1994 | 311 |
| 1995 | 304 |
| 1996 | 260 |
| 1997 | 260 |
| 1998 | 299 |
| 1999 | 206 |
| 2000 | 202 |
| 2001 | 192 |
| 2002 | 123 |
| 2003 | 128 |
| 2004 | 131 |
| 2005 | 103 |
| 2006 | 116 |
| 2007 | 112 |
| 2008 | 88 |
| 2009 | 88 |
| 2010 | 84 |
| 2011 | 52 |
| 2012 | 91 |
| 2013 | 62 |
| 2014 | 78 |
| 2015 | 36 |
| 2016 | 43 |
| 2017 | 54 |
| 2018 | 46 |
| 2019 | 18 |
| 2020 | 6 |
| 2021 | 25 |
| 2022 | 11 |
| 2023 | 18 |
| 2024 | 6 |