Ambiguity

1953 1970 1980 1990 2000 2010
1959 1971 1981 1991 2001  
1967 1972 1982 1992 2002  
1968 1973 1983 1993 2003  
1974 1984 1994 2004  
1975 1985 1995 2005  
1976 1986 1996 2006
1977 1987 1997 2007
1978 1988 1998 2008
1979 1989 1999 2009