| Year | Count |
|---|---|
| 1958 | 34 |
| 1959 | 62 |
| 1960 | 59 |
| 1961 | 37 |
| 1962 | 32 |
| 1963 | 75 |
| 1964 | 44 |
| 1965 | 95 |
| 1966 | 120 |
| 1967 | 126 |
| 1968 | 105 |
| 1969 | 113 |
| 1970 | 81 |
| 1971 | 95 |
| 1972 | 72 |
| 1973 | 116 |
| 1974 | 91 |
| 1975 | 69 |
| 1976 | 79 |
| 1977 | 76 |
| 1978 | 56 |
| 1979 | 66 |
| 1980 | 63 |
| 1981 | 45 |
| 1982 | 62 |
| 1983 | 65 |
| 1984 | 51 |
| 1985 | 39 |
| 1986 | 60 |
| 1987 | 71 |
| 1988 | 71 |
| 1989 | 60 |
| 1990 | 40 |
| 1991 | 51 |
| 1992 | 17 |
| 1993 | 35 |
| 1994 | 107 |
| 1995 | 38 |
| 1996 | 30 |
| 1997 | 5 |
| 2002 | 7 |
| 2003 | 10 |
| 2004 | 20 |
| 2005 | 16 |
| 2007 | 15 |
| 2014 | 6 |
| 2015 | 7 |