Year Annual Number 1970 10 1971 0 1972 0 1973 0 1974 0 1975 354 1976 0 1977 0 1978 0 1979 0 1980 0 1981 0 1982 0 1983 0 1984 0 1985 1312 1986 2400 1987 276 1988 0 1989 0 1990 0 1991 0 1992 0 1993 0 1994 1304 1995 2 1996 0 1997 1 1998 2028 1999 4207 2000 851 2001 41 2002 0 2003 202 2004 0 2005 300 2006 0 2007 6 2008 0