Year	mm Hg
1980	128.2
1981	128.1
1982	127.9
1983	127.7
1984	127.6
1985	127.4
1986	127.4
1987	127.4
1988	127.5
1989	127.6
1990	127.7
1991	127.9
1992	128
1993	128.1
1994	128.1
1995	128.2
1996	128.2
1997	128.3
1998	128.5
1999	128.7
2000	128.9
2001	129.1
2002	129.5
2003	129.8
2004	130.3
2005	130.7
2006	131.2
2007	131.6
2008	132.1