| Year | Count |
|---|---|
| 1979 | 12 |
| 1982 | 6 |
| 1985 | 12 |
| 1986 | 5 |
| 1987 | 10 |
| 1988 | 12 |
| 1989 | 132 |
| 1990 | 157 |
| 1991 | 187 |
| 1992 | 145 |
| 1993 | 158 |
| 1994 | 136 |
| 1995 | 138 |
| 1996 | 154 |
| 1997 | 151 |
| 1998 | 186 |
| 1999 | 439 |
| 2000 | 278 |
| 2001 | 247 |
| 2002 | 224 |
| 2003 | 194 |
| 2004 | 199 |
| 2005 | 225 |
| 2006 | 181 |
| 2007 | 174 |
| 2008 | 153 |
| 2009 | 115 |
| 2010 | 89 |
| 2011 | 94 |
| 2012 | 96 |
| 2013 | 109 |
| 2014 | 77 |
| 2015 | 86 |
| 2016 | 243 |
| 2017 | 222 |
| 2018 | 225 |
| 2019 | 146 |
| 2020 | 146 |
| 2021 | 142 |
| 2022 | 188 |
| 2023 | 220 |
| 2024 | 218 |