| Year | Count |
|---|---|
| 1920 | 5 |
| 1921 | 5 |
| 1927 | 15 |
| 1935 | 18 |
| 1936 | 20 |
| 1938 | 6 |
| 1943 | 5 |
| 1944 | 7 |
| 1947 | 5 |
| 1954 | 6 |
| 1957 | 5 |
| 1958 | 10 |
| 1959 | 15 |
| 1960 | 10 |
| 1962 | 5 |
| 1964 | 5 |
| 1965 | 6 |
| 1967 | 6 |
| 1970 | 10 |
| 1971 | 9 |
| 1972 | 7 |
| 1977 | 11 |
| 1979 | 12 |
| 1980 | 37 |
| 1981 | 5 |
| 1982 | 5 |
| 1983 | 6 |
| 1985 | 5 |
| 1986 | 20 |
| 1987 | 7 |
| 1988 | 40 |
| 1989 | 12 |
| 1990 | 18 |
| 1991 | 22 |
| 1992 | 25 |
| 1993 | 32 |
| 1994 | 10 |
| 1995 | 48 |
| 1996 | 43 |
| 1997 | 64 |
| 1998 | 52 |
| 1999 | 49 |
| 2000 | 17 |
| 2001 | 33 |
| 2002 | 47 |
| 2003 | 22 |
| 2004 | 27 |
| 2005 | 34 |
| 2006 | 11 |
| 2007 | 22 |
| 2009 | 13 |
| 2010 | 15 |
| 2011 | 22 |
| 2016 | 10 |
| 2020 | 12 |
| 2021 | 5 |