| Year | Count |
|---|---|
| 1920 | 6 |
| 1926 | 5 |
| 1927 | 6 |
| 1930 | 6 |
| 1940 | 5 |
| 1942 | 7 |
| 1946 | 7 |
| 1947 | 24 |
| 1948 | 7 |
| 1959 | 14 |
| 1962 | 16 |
| 1964 | 16 |
| 1967 | 12 |
| 1968 | 16 |
| 1969 | 7 |
| 1970 | 6 |
| 1971 | 11 |
| 1972 | 6 |
| 1973 | 8 |
| 1974 | 7 |
| 1975 | 6 |
| 1979 | 5 |
| 1980 | 6 |
| 1981 | 6 |
| 1982 | 5 |
| 1984 | 6 |
| 1986 | 7 |
| 1987 | 8 |
| 1990 | 11 |
| 1991 | 18 |
| 1992 | 11 |
| 1993 | 20 |
| 1994 | 9 |
| 1995 | 7 |
| 1996 | 7 |
| 1997 | 8 |
| 1998 | 12 |
| 1999 | 10 |
| 2000 | 5 |
| 2001 | 42 |
| 2005 | 8 |
| 2006 | 9 |
| 2007 | 7 |
| 2008 | 18 |
| 2009 | 5 |
| 2010 | 12 |
| 2011 | 14 |
| 2012 | 14 |
| 2013 | 12 |
| 2014 | 32 |
| 2015 | 16 |
| 2016 | 12 |
| 2018 | 5 |
| 2019 | 7 |
| 2020 | 5 |
| 2022 | 6 |
| 2023 | 7 |