| Year | Count |
|---|---|
| 1979 | 5 |
| 1980 | 5 |
| 1982 | 12 |
| 1984 | 43 |
| 1985 | 196 |
| 1986 | 281 |
| 1987 | 347 |
| 1988 | 358 |
| 1989 | 344 |
| 1990 | 401 |
| 1991 | 792 |
| 1992 | 775 |
| 1993 | 855 |
| 1994 | 721 |
| 1995 | 644 |
| 1996 | 590 |
| 1997 | 641 |
| 1998 | 667 |
| 1999 | 578 |
| 2000 | 521 |
| 2001 | 576 |
| 2002 | 536 |
| 2003 | 644 |
| 2004 | 702 |
| 2005 | 671 |
| 2006 | 533 |
| 2007 | 508 |
| 2008 | 446 |
| 2009 | 219 |
| 2010 | 237 |
| 2011 | 244 |
| 2012 | 176 |
| 2013 | 167 |
| 2014 | 194 |
| 2015 | 173 |
| 2016 | 144 |
| 2017 | 182 |
| 2018 | 77 |
| 2019 | 45 |
| 2020 | 55 |
| 2021 | 34 |
| 2022 | 39 |
| 2023 | 22 |
| 2024 | 30 |