| Year | Count |
|---|---|
| 1952 | 6 |
| 1956 | 6 |
| 1957 | 8 |
| 1959 | 10 |
| 1960 | 5 |
| 1962 | 11 |
| 1963 | 8 |
| 1964 | 11 |
| 1965 | 7 |
| 1966 | 5 |
| 1967 | 5 |
| 1968 | 7 |
| 1969 | 6 |
| 1971 | 9 |
| 1972 | 10 |
| 1973 | 11 |
| 1974 | 8 |
| 1976 | 10 |
| 1977 | 5 |
| 1980 | 6 |
| 1982 | 8 |
| 1985 | 8 |
| 1990 | 5 |
| 1992 | 5 |
| 1993 | 7 |
| 1994 | 5 |
| 1996 | 11 |
| 1999 | 6 |
| 2002 | 10 |
| 2003 | 10 |
| 2004 | 10 |
| 2007 | 12 |
| 2014 | 6 |
| 2016 | 12 |