| Year | Count |
|---|---|
| 1961 | 5 |
| 1963 | 9 |
| 1964 | 28 |
| 1965 | 27 |
| 1966 | 25 |
| 1967 | 22 |
| 1968 | 24 |
| 1969 | 27 |
| 1970 | 11 |
| 1971 | 14 |
| 1972 | 10 |
| 1973 | 5 |
| 1974 | 13 |
| 1976 | 12 |
| 1978 | 5 |
| 1979 | 10 |
| 1993 | 60 |
| 1994 | 89 |
| 1995 | 48 |
| 1996 | 20 |
| 1997 | 43 |
| 1998 | 46 |
| 2000 | 21 |
| 2001 | 12 |
| 2002 | 5 |
| 2003 | 5 |
| 2004 | 21 |
| 2005 | 46 |
| 2006 | 48 |
| 2007 | 50 |
| 2008 | 41 |
| 2009 | 6 |
| 2010 | 64 |
| 2011 | 46 |
| 2012 | 16 |
| 2013 | 12 |
| 2014 | 6 |
| 2015 | 58 |
| 2016 | 17 |
| 2017 | 19 |
| 2018 | 8 |
| 2021 | 13 |
| 2022 | 15 |
| 2024 | 10 |