Year Number 1961 100.63162184189079 1962 105.7178631051753 1963 111.03507271171942 1964 116.57167908811925 1965 122.44714349977508 1966 128.60572483841182 1967 135.16483516483518 1968 143.66336633663366 1969 151.3360739979445 1970 163.95232815964522 1971 169.5578231292517 1972 175.507835171213 1973 181.53206650831356 1974 187.95620437956205 1975 194.70074812967582 1976 201.79028132992326 1977 209.25196850393698 1978 217.11590296495956 1979 225.57172557172555 1980 234.3406985032074 1981 239.07714491708725 1982 244.16058394160584 1983 249.26144756277697 1984 254.11061285500747 1985 261.7246596066566 1986 269.6788990825688 1987 268.78388845855926 1988 267.45098039215685 1989 266.5075576770088 1990 264.33521353746977 1991 261.5629984051037 1992 260.45777426992896 1993 257.8125 1994 255.22041763341065 1995 252.67993874425727 1996 250.18953752843066 1997 254.05851462865718 1998 257.8470675575353 1999 261.56502571638504 2000 265.5863073561544 2001 264.81481481481484 2002 264.04779145546706 2003 263.2851985559567 2004 262.5269978401728 2005 261.96120689655174 2006 261.2106017191977 2007 247.0528455284553 2008 199.6987951807229