| Year | Count |
|---|---|
| 1982 | 14 |
| 1991 | 10 |
| 1992 | 12 |
| 1993 | 70 |
| 1994 | 164 |
| 1995 | 140 |
| 1996 | 235 |
| 1997 | 279 |
| 1998 | 269 |
| 1999 | 296 |
| 2000 | 261 |
| 2001 | 381 |
| 2002 | 278 |
| 2003 | 260 |
| 2004 | 355 |
| 2005 | 316 |
| 2006 | 285 |
| 2007 | 396 |
| 2008 | 421 |
| 2009 | 245 |
| 2010 | 199 |
| 2011 | 116 |
| 2012 | 74 |
| 2013 | 63 |
| 2014 | 11 |
| 2015 | 32 |
| 2016 | 34 |
| 2017 | 8 |