Antecedent

1946	1972	1980	1990	2000	2010
1950	1973	1983	1991	2001
	1975	1986	1993	2002
	1976	1987	1994	2003
	1977	1988	1995	2004
	1978	1989	1996	2005
			1998	2006
			1999	2007
				2008
				2009