Year	mm Hg
1980	130.2
1981	130.1
1982	129.9
1983	129.6
1984	129.3
1985	129
1986	128.7
1987	128.5
1988	128.3
1989	128.1
1990	127.9
1991	127.7
1992	127.5
1993	127.3
1994	127.2
1995	127.1
1996	127
1997	126.9
1998	126.9
1999	126.9
2000	126.9
2001	127
2002	127.1
2003	127.2
2004	127.4
2005	127.5
2006	127.7
2007	128
2008	128.2