| Year | Count |
|---|---|
| 1976 | 18 |
| 1977 | 5 |
| 1978 | 5 |
| 1979 | 5 |
| 1981 | 12 |
| 1984 | 5 |
| 1986 | 17 |
| 1988 | 10 |
| 1992 | 50 |
| 1993 | 22 |
| 1994 | 29 |
| 1995 | 76 |
| 1996 | 93 |
| 1997 | 166 |
| 1998 | 219 |
| 1999 | 478 |
| 2000 | 607 |
| 2001 | 781 |
| 2002 | 1,017 |
| 2003 | 1,420 |
| 2004 | 2,358 |
| 2004 | 14 |
| 2005 | 2,626 |
| 2006 | 3,237 |
| 2007 | 3,427 |
| 2008 | 3,780 |
| 2009 | 3,823 |
| 2010 | 3,843 |
| 2011 | 4,844 |
| 2012 | 5,147 |
| 2013 | 5,061 |
| 2014 | 4,912 |
| 2015 | 4,776 |
| 2016 | 4,913 |
| 2017 | 4,567 |
| 2018 | 4,168 |
| 2019 | 3,989 |
| 2020 | 3,749 |
| 2021 | 3,666 |
| 2022 | 3,552 |
| 2023 | 3,267 |
| 2024 | 2,858 |