Year	mm Hg
1980	132.5
1981	132.3
1982	132.1
1983	131.8
1984	131.5
1985	131.3
1986	130.9
1987	130.6
1988	130.2
1989	129.8
1990	129.5
1991	129.2
1992	128.9
1993	128.5
1994	128.2
1995	127.8
1996	127.4
1997	127.1
1998	126.7
1999	126.3
2000	125.9
2001	125.5
2002	125.1
2003	124.8
2004	124.5
2005	124.2
2006	123.9
2007	123.6
2008	123.3