| Year | Count |
|---|---|
| 1934 | 5 |
| 1935 | 5 |
| 1937 | 6 |
| 1939 | 6 |
| 1941 | 7 |
| 1942 | 7 |
| 1943 | 5 |
| 1944 | 8 |
| 1946 | 5 |
| 1947 | 5 |
| 1964 | 5 |
| 1973 | 6 |
| 1975 | 6 |
| 1978 | 6 |
| 1979 | 6 |
| 1980 | 20 |
| 1981 | 7 |
| 1982 | 7 |
| 1985 | 24 |
| 1986 | 7 |
| 1987 | 5 |
| 1988 | 11 |
| 1990 | 5 |
| 1991 | 7 |
| 1992 | 5 |
| 1994 | 5 |
| 1995 | 19 |
| 1997 | 6 |
| 1998 | 5 |
| 1999 | 24 |
| 2000 | 32 |
| 2001 | 52 |
| 2002 | 50 |
| 2003 | 46 |
| 2004 | 88 |
| 2005 | 70 |
| 2006 | 74 |
| 2007 | 83 |
| 2008 | 106 |
| 2009 | 129 |
| 2010 | 165 |
| 2011 | 103 |
| 2012 | 183 |
| 2013 | 111 |
| 2014 | 54 |
| 2015 | 105 |
| 2016 | 137 |
| 2017 | 94 |
| 2018 | 116 |
| 2019 | 35 |
| 2020 | 48 |
| 2021 | 33 |
| 2022 | 44 |
| 2023 | 41 |
| 2024 | 46 |