| Year | Count |
|---|---|
| 1985 | 5 |
| 1986 | 7 |
| 1987 | 10 |
| 1988 | 6 |
| 1989 | 12 |
| 1991 | 9 |
| 1994 | 6 |
| 1995 | 27 |
| 1996 | 12 |
| 1997 | 19 |
| 1998 | 24 |
| 1999 | 63 |
| 2000 | 64 |
| 2001 | 59 |
| 2002 | 66 |
| 2003 | 116 |
| 2004 | 395 |
| 2005 | 472 |
| 2006 | 543 |
| 2007 | 463 |
| 2008 | 417 |
| 2009 | 436 |
| 2010 | 457 |
| 2011 | 442 |
| 2012 | 1,453 |
| 2013 | 5,797 |
| 2014 | 4,552 |
| 2015 | 3,267 |
| 2016 | 2,323 |
| 2017 | 1,439 |
| 2018 | 1,208 |
| 2019 | 911 |
| 2020 | 747 |
| 2021 | 804 |
| 2022 | 659 |
| 2023 | 492 |
| 2024 | 486 |