| Year | Count |
|---|---|
| 1931 | 5 |
| 1948 | 5 |
| 1950 | 11 |
| 1951 | 6 |
| 1953 | 7 |
| 1954 | 10 |
| 1955 | 5 |
| 1957 | 24 |
| 1958 | 20 |
| 1959 | 28 |
| 1960 | 18 |
| 1961 | 5 |
| 1963 | 10 |
| 1965 | 8 |
| 1967 | 10 |
| 1968 | 7 |
| 1970 | 9 |
| 1971 | 9 |
| 1974 | 6 |
| 1977 | 10 |
| 1978 | 10 |
| 1981 | 8 |
| 1984 | 5 |
| 1985 | 5 |
| 1986 | 5 |
| 1990 | 8 |
| 1991 | 5 |
| 1992 | 5 |
| 1993 | 8 |
| 1994 | 5 |
| 1995 | 6 |
| 1997 | 8 |
| 1998 | 6 |
| 1999 | 6 |
| 2000 | 7 |
| 2001 | 9 |
| 2002 | 9 |
| 2004 | 13 |
| 2005 | 7 |
| 2006 | 10 |
| 2007 | 9 |
| 2010 | 7 |
| 2011 | 6 |
| 2012 | 7 |
| 2013 | 6 |
| 2014 | 5 |
| 2015 | 27 |
| 2016 | 24 |
| 2017 | 36 |
| 2018 | 12 |
| 2019 | 24 |
| 2020 | 18 |
| 2022 | 20 |
| 2023 | 12 |
| 2024 | 18 |