Year	mm Hg
1980	126.5
1981	126.6
1982	126.7
1983	126.8
1984	126.9
1985	126.9
1986	127
1987	127.1
1988	127.2
1989	127.3
1990	127.3
1991	127.3
1992	127.3
1993	127.2
1994	127.2
1995	127.1
1996	127
1997	126.9
1998	126.9
1999	126.8
2000	126.7
2001	126.7
2002	126.7
2003	126.6
2004	126.6
2005	126.6
2006	126.6
2007	126.6
2008	126.5