| Year | Count |
|---|---|
| 1977 | 20 |
| 1983 | 10 |
| 1986 | 16 |
| 1987 | 5 |
| 1988 | 43 |
| 1989 | 24 |
| 1990 | 103 |
| 1991 | 72 |
| 1992 | 138 |
| 1993 | 132 |
| 1994 | 238 |
| 1995 | 339 |
| 1996 | 323 |
| 1997 | 377 |
| 1998 | 345 |
| 1999 | 374 |
| 2000 | 344 |
| 2001 | 339 |
| 2002 | 292 |
| 2003 | 186 |
| 2004 | 356 |
| 2005 | 279 |
| 2006 | 336 |
| 2007 | 288 |
| 2008 | 272 |
| 2009 | 167 |
| 2010 | 143 |
| 2011 | 160 |
| 2012 | 71 |
| 2013 | 60 |
| 2014 | 39 |
| 2015 | 60 |
| 2016 | 61 |
| 2017 | 63 |
| 2018 | 41 |
| 2019 | 32 |
| 2020 | 78 |
| 2021 | 68 |
| 2022 | 74 |
| 2023 | 64 |
| 2024 | 98 |