Year	mm Hg
1980	130
1981	129.5
1982	129
1983	128.6
1984	128.2
1985	127.7
1986	127.4
1987	127.1
1988	126.8
1989	126.5
1990	126.2
1991	126
1992	125.8
1993	125.5
1994	125.2
1995	124.8
1996	124.5
1997	124.1
1998	123.7
1999	123.3
2000	122.9
2001	122.5
2002	122.1
2003	121.7
2004	121.3
2005	120.9
2006	120.4
2007	120
2008	119.6