| Year | Count |
|---|---|
| 1968 | 5 |
| 1985 | 5 |
| 1988 | 5 |
| 1989 | 7 |
| 1990 | 13 |
| 1991 | 6 |
| 1992 | 32 |
| 1993 | 10 |
| 1994 | 14 |
| 1995 | 53 |
| 1996 | 53 |
| 1997 | 85 |
| 1998 | 174 |
| 1999 | 356 |
| 2000 | 337 |
| 2001 | 604 |
| 2002 | 596 |
| 2003 | 653 |
| 2004 | 614 |
| 2005 | 906 |
| 2006 | 896 |
| 2007 | 957 |
| 2008 | 1,014 |
| 2009 | 1,146 |
| 2010 | 1,371 |
| 2011 | 2,410 |
| 2012 | 3,233 |
| 2013 | 3,648 |
| 2014 | 3,876 |
| 2015 | 4,466 |
| 2016 | 4,682 |
| 2017 | 6 |
| 2017 | 4,472 |
| 2018 | 5,011 |
| 2019 | 5,152 |
| 2020 | 4,054 |
| 2021 | 6 |
| 2021 | 4,345 |
| 2022 | 3,873 |
| 2023 | 3,175 |
| 2024 | 3,111 |