Year	mm Hg
1980	131
1981	130.9
1982	130.7
1983	130.5
1984	130.3
1985	130.1
1986	130
1987	129.9
1988	129.9
1989	129.9
1990	129.8
1991	129.7
1992	129.5
1993	129.3
1994	129
1995	128.8
1996	128.4
1997	128
1998	127.6
1999	127.2
2000	126.8
2001	126.5
2002	126
2003	125.6
2004	125.2
2005	124.8
2006	124.4
2007	124
2008	123.6