Year	mm Hg
1980	127.7
1981	127.8
1982	127.9
1983	127.9
1984	128
1985	128.1
1986	128.3
1987	128.3
1988	128.4
1989	128.4
1990	128.5
1991	128.5
1992	128.6
1993	128.6
1994	128.7
1995	128.7
1996	128.8
1997	128.8
1998	128.9
1999	129
2000	129.1
2001	129.3
2002	129.3
2003	129.5
2004	129.6
2005	129.8
2006	129.9
2007	130.1
2008	130.3