Year	mm Hg
1980	131.2
1981	130.9
1982	130.5
1983	130.1
1984	129.7
1985	129.3
1986	129
1987	128.7
1988	128.6
1989	128.5
1990	128.4
1991	128.4
1992	128.3
1993	128.2
1994	128.1
1995	127.9
1996	127.6
1997	127.3
1998	126.9
1999	126.4
2000	125.9
2001	125.4
2002	124.9
2003	124.4
2004	123.9
2005	123.3
2006	122.8
2007	122.3
2008	121.8