| Year | Count |
|---|---|
| 1991 | 5 |
| 1992 | 11 |
| 1993 | 10 |
| 1994 | 16 |
| 1995 | 34 |
| 1996 | 12 |
| 1997 | 68 |
| 1998 | 64 |
| 1999 | 63 |
| 2000 | 81 |
| 2001 | 74 |
| 2002 | 90 |
| 2003 | 250 |
| 2004 | 238 |
| 2005 | 264 |
| 2006 | 247 |
| 2007 | 280 |
| 2008 | 322 |
| 2009 | 333 |
| 2010 | 262 |
| 2011 | 239 |
| 2012 | 251 |
| 2013 | 265 |
| 2014 | 244 |
| 2015 | 227 |
| 2016 | 257 |
| 2017 | 244 |
| 2018 | 216 |
| 2019 | 97 |
| 2020 | 60 |
| 2021 | 51 |
| 2022 | 56 |
| 2023 | 12 |
| 2024 | 16 |