Year	mm Hg
1980	125.9
1981	125.9
1982	125.9
1983	125.9
1984	125.9
1985	125.9
1986	125.9
1987	126
1988	126
1989	126
1990	126
1991	126
1992	125.9
1993	125.9
1994	125.9
1995	125.8
1996	125.8
1997	125.7
1998	125.7
1999	125.7
2000	125.6
2001	125.4
2002	125.2
2003	125.1
2004	124.8
2005	124.6
2006	124.3
2007	124
2008	123.6