Year	mm Hg
1980	127.8
1981	127.4
1982	127.1
1983	126.7
1984	126.3
1985	126
1986	125.8
1987	125.5
1988	125.3
1989	125.1
1990	124.9
1991	124.7
1992	124.6
1993	124.4
1994	124.3
1995	124.2
1996	124.2
1997	124.1
1998	124.1
1999	124.2
2000	124.3
2001	124.4
2002	124.6
2003	124.8
2004	125
2005	125.3
2006	125.7
2007	126.1
2008	126.5