Year	mm Hg
1980	132.2
1981	131.9
1982	131.5
1983	131.1
1984	130.7
1985	130.3
1986	129.9
1987	129.6
1988	129.2
1989	128.9
1990	128.5
1991	128.3
1992	128
1993	127.7
1994	127.4
1995	127
1996	126.7
1997	126.4
1998	126.1
1999	125.8
2000	125.5
2001	125.3
2002	125
2003	124.7
2004	124.5
2005	124.3
2006	124.1
2007	123.9
2008	123.7