| Year | Count |
|---|---|
| 1981 | 14 |
| 1982 | 6 |
| 1983 | 14 |
| 1984 | 8 |
| 1985 | 12 |
| 1986 | 12 |
| 1987 | 15 |
| 1988 | 12 |
| 1989 | 18 |
| 1990 | 25 |
| 1991 | 27 |
| 1992 | 22 |
| 1993 | 38 |
| 1994 | 865 |
| 1995 | 844 |
| 1996 | 764 |
| 1997 | 1,014 |
| 1998 | 1,116 |
| 1999 | 878 |
| 2000 | 1,083 |
| 2001 | 1,462 |
| 2002 | 1,585 |
| 2003 | 1,491 |
| 2004 | 1,915 |
| 2004 | 12 |
| 2005 | 1,890 |
| 2006 | 1,755 |
| 2007 | 1,913 |
| 2008 | 2,030 |
| 2009 | 2,024 |
| 2010 | 2,185 |
| 2011 | 2,622 |
| 2012 | 2,552 |
| 2013 | 2,102 |
| 2014 | 1,908 |
| 2015 | 2,194 |
| 2016 | 2,292 |
| 2017 | 2,150 |
| 2018 | 1,900 |
| 2019 | 1,724 |
| 2020 | 1,476 |
| 2021 | 1,509 |
| 2022 | 1,492 |
| 2023 | 1,495 |
| 2024 | 1,386 |