| Year | Count |
|---|---|
| 1980 | 6 |
| 1986 | 14 |
| 1987 | 22 |
| 1988 | 36 |
| 1989 | 17 |
| 1990 | 60 |
| 1991 | 132 |
| 1992 | 160 |
| 1993 | 98 |
| 1994 | 181 |
| 1995 | 166 |
| 1996 | 214 |
| 1997 | 252 |
| 1998 | 346 |
| 1999 | 302 |
| 2000 | 339 |
| 2001 | 271 |
| 2002 | 349 |
| 2003 | 422 |
| 2004 | 564 |
| 2005 | 688 |
| 2006 | 667 |
| 2007 | 832 |
| 2008 | 796 |
| 2009 | 759 |
| 2010 | 948 |
| 2011 | 1,254 |
| 2012 | 1,508 |
| 2013 | 1,348 |
| 2014 | 1,445 |
| 2015 | 1,334 |
| 2016 | 1,154 |
| 2017 | 991 |
| 2018 | 951 |
| 2019 | 854 |
| 2020 | 929 |
| 2021 | 728 |
| 2022 | 683 |
| 2023 | 576 |
| 2024 | 534 |