| Year | Count |
|---|---|
| 1987 | 16 |
| 1988 | 40 |
| 1989 | 5 |
| 1991 | 18 |
| 1992 | 29 |
| 1993 | 36 |
| 1994 | 15 |
| 1995 | 28 |
| 1996 | 72 |
| 1997 | 246 |
| 1998 | 364 |
| 1999 | 196 |
| 2000 | 409 |
| 2001 | 564 |
| 2002 | 421 |
| 2003 | 385 |
| 2004 | 886 |
| 2005 | 982 |
| 2006 | 1,034 |
| 2007 | 861 |
| 2008 | 622 |
| 2009 | 393 |
| 2010 | 435 |
| 2011 | 448 |
| 2012 | 466 |
| 2013 | 327 |
| 2014 | 265 |
| 2015 | 433 |
| 2016 | 458 |
| 2017 | 455 |
| 2018 | 397 |
| 2019 | 344 |
| 2020 | 339 |
| 2021 | 313 |
| 2022 | 416 |
| 2023 | 539 |
| 2024 | 487 |