Year	mm Hg
1980	132.9
1981	132.4
1982	132
1983	131.5
1984	131
1985	130.6
1986	130.2
1987	130
1988	129.7
1989	129.5
1990	129.3
1991	129
1992	128.8
1993	128.5
1994	128.2
1995	127.8
1996	127.4
1997	127
1998	126.6
1999	126.2
2000	125.8
2001	125.4
2002	125.1
2003	124.7
2004	124.3
2005	124
2006	123.6
2007	123.3
2008	122.9