| Year | Count |
|---|---|
| 1972 | 6 |
| 1974 | 5 |
| 1975 | 5 |
| 1976 | 12 |
| 1984 | 5 |
| 1993 | 7 |
| 1996 | 39 |
| 1997 | 59 |
| 1998 | 70 |
| 1999 | 69 |
| 2000 | 54 |
| 2001 | 63 |
| 2002 | 53 |
| 2003 | 72 |
| 2004 | 73 |
| 2005 | 44 |
| 2006 | 42 |
| 2007 | 60 |
| 2008 | 48 |
| 2009 | 38 |
| 2010 | 43 |
| 2011 | 25 |
| 2012 | 27 |
| 2013 | 27 |
| 2014 | 20 |
| 2015 | 36 |
| 2016 | 51 |
| 2017 | 30 |
| 2018 | 13 |
| 2019 | 16 |
| 2020 | 14 |
| 2022 | 10 |