Year	mm Hg
1980	129.5
1981	128.9
1982	128.4
1983	128
1984	127.6
1985	127.2
1986	126.9
1987	126.6
1988	126.5
1989	126.4
1990	126.3
1991	126.3
1992	126.2
1993	126.1
1994	126
1995	125.9
1996	125.9
1997	125.8
1998	125.7
1999	125.6
2000	125.5
2001	125.4
2002	125.3
2003	125.2
2004	125.1
2005	124.9
2006	124.8
2007	124.7
2008	124.5