Year	mm Hg
1980	133.7
1981	133.2
1982	132.7
1983	132.2
1984	131.7
1985	131.2
1986	130.8
1987	130.4
1988	130.1
1989	129.9
1990	129.6
1991	129.4
1992	129.2
1993	129
1994	128.7
1995	128.3
1996	127.9
1997	127.5
1998	127
1999	126.5
2000	126.1
2001	125.6
2002	125.1
2003	124.6
2004	124.2
2005	123.7
2006	123.3
2007	122.8
2008	122.4