Year	mm Hg
1980	116.6
1981	116.8
1982	117
1983	117.2
1984	117.4
1985	117.5
1986	117.7
1987	117.9
1988	118.1
1989	118.3
1990	118.5
1991	118.8
1992	119.1
1993	119.4
1994	119.7
1995	120.1
1996	120.5
1997	120.8
1998	121
1999	121.2
2000	121.4
2001	121.5
2002	121.7
2003	121.9
2004	122
2005	122.2
2006	122.4
2007	122.6
2008	122.7