Year	mm Hg
1980	130.6
1981	130.6
1982	130.6
1983	130.6
1984	130.6
1985	130.6
1986	130.6
1987	130.7
1988	130.8
1989	130.8
1990	130.9
1991	130.9
1992	131
1993	131
1994	131
1995	131
1996	131
1997	130.9
1998	130.9
1999	130.8
2000	130.7
2001	130.7
2002	130.7
2003	130.7
2004	130.7
2005	130.7
2006	130.8
2007	130.8
2008	130.9
