| Year | Count |
|---|---|
| 1965 | 24 |
| 1966 | 7 |
| 1967 | 23 |
| 1968 | 66 |
| 1969 | 108 |
| 1970 | 192 |
| 1971 | 300 |
| 1972 | 286 |
| 1973 | 453 |
| 1974 | 473 |
| 1975 | 552 |
| 1976 | 404 |
| 1977 | 623 |
| 1978 | 499 |
| 1979 | 429 |
| 1980 | 454 |
| 1981 | 357 |
| 1982 | 193 |
| 1983 | 200 |
| 1984 | 103 |
| 1985 | 111 |
| 1986 | 110 |
| 1987 | 74 |
| 1988 | 55 |
| 1989 | 54 |
| 1990 | 49 |
| 1991 | 19 |
| 1992 | 16 |
| 1993 | 12 |
| 1994 | 18 |
| 2001 | 10 |