| Year | Count |
|---|---|
| 1959 | 16 |
| 1963 | 28 |
| 1964 | 24 |
| 1964 | 41 |
| 1966 | 7 |
| 1967 | 5 |
| 1968 | 6 |
| 1969 | 11 |
| 1970 | 6 |
| 1970 | 6 |
| 1972 | 10 |
| 1973 | 5 |
| 1974 | 12 |
| 1975 | 44 |
| 1976 | 472 |
| 1976 | 5 |
| 1977 | 439 |
| 1978 | 290 |
| 1979 | 278 |
| 1980 | 195 |
| 1981 | 161 |
| 1981 | 6 |
| 1982 | 135 |
| 1983 | 113 |
| 1984 | 67 |
| 1985 | 165 |
| 1986 | 554 |
| 1987 | 776 |
| 1988 | 648 |
| 1989 | 594 |
| 1990 | 484 |
| 1991 | 517 |
| 1992 | 338 |
| 1993 | 337 |
| 1994 | 219 |
| 1995 | 138 |
| 1996 | 114 |
| 1997 | 74 |
| 1998 | 43 |
| 1999 | 65 |
| 2000 | 32 |
| 2001 | 27 |
| 2002 | 17 |
| 2003 | 20 |
| 2004 | 44 |
| 2005 | 28 |
| 2006 | 29 |
| 2007 | 8 |
| 2008 | 16 |
| 2010 | 8 |
| 2011 | 15 |