Year	mm Hg
1980	136.6
1981	136
1982	135.3
1983	134.6
1984	133.9
1985	133.3
1986	132.7
1987	132.1
1988	131.7
1989	131.2
1990	130.8
1991	130.3
1992	129.9
1993	129.4
1994	128.9
1995	128.3
1996	127.8
1997	127.2
1998	126.7
1999	126.1
2000	125.6
2001	125.1
2002	124.6
2003	124.2
2004	123.7
2005	123.2
2006	122.8
2007	122.3
2008	121.8