Year	mm Hg
1980	130.8
1981	130.5
1982	130.2
1983	130
1984	129.6
1985	129.3
1986	129
1987	128.8
1988	128.5
1989	128.2
1990	127.9
1991	127.2
1992	126.8
1993	126.5
1994	126.2
1995	125.9
1996	125.8
1997	125.7
1998	125.8
1999	125.9
2000	126.1
2001	126.4
2002	126.6
2003	126.7
2004	126.8
2005	126.9
2006	127.1
2007	127.2
2008	127.4