| Year | Count |
|---|---|
| 1985 | 12 |
| 1986 | 11 |
| 1987 | 13 |
| 1988 | 19 |
| 1989 | 16 |
| 1990 | 15 |
| 1991 | 24 |
| 1992 | 40 |
| 1993 | 73 |
| 1994 | 76 |
| 1995 | 70 |
| 1996 | 103 |
| 1997 | 119 |
| 1998 | 143 |
| 1999 | 214 |
| 2000 | 336 |
| 2001 | 332 |
| 2002 | 354 |
| 2003 | 408 |
| 2004 | 403 |
| 2005 | 428 |
| 2006 | 427 |
| 2007 | 466 |
| 2008 | 446 |
| 2009 | 478 |
| 2010 | 478 |
| 2011 | 481 |
| 2012 | 459 |
| 2013 | 402 |
| 2014 | 345 |
| 2015 | 347 |
| 2016 | 1,008 |
| 2017 | 867 |
| 2018 | 939 |
| 2019 | 616 |
| 2020 | 578 |
| 2021 | 654 |
| 2022 | 580 |
| 2023 | 582 |
| 2024 | 508 |