| Year | Count |
|---|---|
| 1965 | 15 |
| 1967 | 5 |
| 1968 | 19 |
| 1969 | 5 |
| 1970 | 11 |
| 1971 | 5 |
| 1973 | 12 |
| 1974 | 12 |
| 1975 | 40 |
| 1976 | 79 |
| 1977 | 25 |
| 1978 | 78 |
| 1979 | 58 |
| 1980 | 24 |
| 1981 | 56 |
| 1982 | 80 |
| 1983 | 106 |
| 1984 | 96 |
| 1985 | 154 |
| 1986 | 187 |
| 1987 | 188 |
| 1988 | 216 |
| 1989 | 210 |
| 1990 | 164 |
| 1991 | 191 |
| 1992 | 121 |
| 1993 | 61 |
| 1994 | 37 |
| 1995 | 54 |
| 1996 | 28 |
| 1997 | 17 |
| 1998 | 24 |
| 1999 | 11 |
| 2002 | 10 |
| 2004 | 10 |
| 2007 | 5 |