| Year | Count |
|---|---|
| 1949 | 10 |
| 1956 | 10 |
| 1960 | 7 |
| 1961 | 12 |
| 1962 | 15 |
| 1963 | 10 |
| 1964 | 16 |
| 1965 | 17 |
| 1966 | 7 |
| 1967 | 25 |
| 1968 | 34 |
| 1969 | 45 |
| 1970 | 29 |
| 1971 | 46 |
| 1972 | 63 |
| 1973 | 31 |
| 1974 | 27 |
| 1975 | 39 |
| 1976 | 15 |
| 1981 | 15 |
| 1984 | 10 |
| 1985 | 10 |
| 1986 | 5 |
| 1989 | 5 |
| 1990 | 6 |
| 1991 | 46 |
| 1992 | 38 |
| 1993 | 43 |
| 1994 | 44 |
| 1995 | 6 |
| 1996 | 23 |
| 1997 | 12 |
| 1998 | 29 |
| 1999 | 5 |
| 2000 | 20 |
| 2002 | 14 |
| 2004 | 10 |
| 2005 | 10 |
| 2009 | 10 |
| 2012 | 15 |
| 2013 | 5 |
| 2017 | 5 |