| Year | Count |
|---|---|
| 1986 | 10 |
| 1987 | 7 |
| 1989 | 15 |
| 1990 | 13 |
| 1991 | 8 |
| 1992 | 8 |
| 1993 | 8 |
| 1994 | 32 |
| 1995 | 14 |
| 1996 | 58 |
| 1997 | 184 |
| 1998 | 319 |
| 1999 | 227 |
| 2000 | 204 |
| 2001 | 225 |
| 2002 | 187 |
| 2003 | 253 |
| 2004 | 275 |
| 2005 | 359 |
| 2006 | 309 |
| 2007 | 322 |
| 2008 | 334 |
| 2009 | 282 |
| 2010 | 203 |
| 2011 | 277 |
| 2012 | 316 |
| 2013 | 271 |
| 2014 | 242 |
| 2015 | 303 |
| 2016 | 425 |
| 2017 | 382 |
| 2018 | 261 |
| 2019 | 258 |
| 2020 | 190 |
| 2021 | 287 |
| 2022 | 313 |
| 2023 | 301 |
| 2024 | 283 |