| Year | Count |
|---|---|
| 1946 | 10 |
| 1959 | 12 |
| 1960 | 34 |
| 1961 | 36 |
| 1962 | 87 |
| 1963 | 39 |
| 1964 | 190 |
| 1965 | 442 |
| 1966 | 368 |
| 1967 | 293 |
| 1968 | 257 |
| 1969 | 247 |
| 1970 | 167 |
| 1971 | 139 |
| 1972 | 76 |
| 1973 | 84 |
| 1974 | 71 |
| 1975 | 48 |
| 1976 | 51 |
| 1977 | 23 |
| 1978 | 22 |
| 1979 | 64 |
| 1980 | 51 |
| 1981 | 45 |
| 1982 | 55 |
| 1983 | 59 |
| 1984 | 57 |
| 1985 | 66 |
| 1986 | 18 |
| 1987 | 45 |
| 1988 | 69 |
| 1989 | 59 |
| 1990 | 68 |
| 1991 | 61 |
| 1992 | 64 |
| 1993 | 36 |
| 1994 | 41 |
| 1995 | 30 |
| 1996 | 35 |
| 1997 | 30 |
| 1998 | 28 |
| 1999 | 32 |
| 2000 | 25 |
| 2001 | 22 |
| 2003 | 7 |
| 2004 | 15 |
| 2005 | 14 |
| 2006 | 21 |
| 2007 | 5 |
| 2008 | 11 |
| 2009 | 12 |
| 2010 | 22 |
| 2014 | 10 |