| Year | Count |
|---|---|
| 1915 | 10 |
| 1916 | 7 |
| 1917 | 7 |
| 1918 | 6 |
| 1919 | 5 |
| 1920 | 5 |
| 1921 | 8 |
| 1922 | 16 |
| 1923 | 12 |
| 1924 | 14 |
| 1936 | 5 |
| 1946 | 7 |
| 1950 | 5 |
| 1952 | 7 |
| 1953 | 6 |
| 1956 | 8 |
| 1957 | 10 |
| 1958 | 10 |
| 1959 | 16 |
| 1961 | 6 |
| 1962 | 7 |
| 1970 | 8 |
| 1973 | 5 |
| 1975 | 5 |
| 1981 | 13 |
| 1982 | 5 |
| 1983 | 6 |
| 1984 | 11 |
| 1985 | 8 |
| 1988 | 12 |
| 1989 | 5 |
| 1990 | 15 |
| 1991 | 14 |
| 1992 | 17 |
| 1993 | 9 |
| 1994 | 7 |
| 1995 | 11 |
| 1996 | 5 |
| 1997 | 5 |
| 1998 | 14 |
| 1999 | 7 |
| 2000 | 13 |
| 2001 | 11 |
| 2002 | 8 |
| 2003 | 7 |
| 2004 | 7 |
| 2005 | 6 |
| 2007 | 8 |
| 2008 | 5 |
| 2009 | 8 |
| 2010 | 13 |
| 2011 | 5 |
| 2012 | 6 |
| 2014 | 7 |
| 2016 | 18 |