Year	mm Hg
1980	133.8
1981	133.8
1982	133.8
1983	133.8
1984	133.7
1985	133.6
1986	133.5
1987	133.3
1988	133
1989	132.7
1990	132.3
1991	131.9
1992	131.4
1993	130.9
1994	130.4
1995	129.9
1996	129.5
1997	129.2
1998	128.9
1999	128.6
2000	128.5
2001	128.4
2002	128.4
2003	128.4
2004	128.4
2005	128.4
2006	128.5
2007	128.5
2008	128.5