| Year | Count |
|---|---|
| 1981 | 6 |
| 1984 | 5 |
| 1985 | 5 |
| 1987 | 6 |
| 1988 | 17 |
| 1989 | 15 |
| 1990 | 40 |
| 1991 | 48 |
| 1992 | 44 |
| 1993 | 35 |
| 1994 | 66 |
| 1995 | 85 |
| 1996 | 112 |
| 1997 | 194 |
| 1998 | 155 |
| 1999 | 113 |
| 2000 | 224 |
| 2001 | 284 |
| 2002 | 271 |
| 2003 | 302 |
| 2004 | 373 |
| 2005 | 491 |
| 2006 | 582 |
| 2007 | 470 |
| 2008 | 464 |
| 2009 | 475 |
| 2010 | 554 |
| 2011 | 551 |
| 2012 | 705 |
| 2013 | 691 |
| 2014 | 691 |
| 2015 | 915 |
| 2016 | 944 |
| 2017 | 972 |
| 2018 | 749 |
| 2019 | 698 |
| 2020 | 755 |
| 2021 | 908 |
| 2022 | 900 |
| 2023 | 824 |
| 2024 | 776 |