Year	base year varies by country
1961	10.439490147944747
1962	10.414721330726703
1963	10.531887385284303
1964	10.655532173703337
1965	10.849168608831782
1966	11.627845104786601
1967	12.421508984773839
1968	12.875670935008682
1969	13.313326633575093
1970	13.921888470373572
1971	14.649150765592346
1972	15.61417840301833
1973	17.062934790975646
1974	19.223101525027737
1975	21.96498505220982
1976	24.669889291615174
1977	25.61009914035961
1978	26.63008147341434
1979	28.992689905940022
1980	32.62152154351578
1981	35.37601547079345
1982	37.54821251826928
1983	43.08144571473531
1984	45.71757369333679
1985	47.70236196950523
1986	49.95783506973581
1987	52.44515983016118
1988	55.05063075876322
1989	57.864403745564566
1990	61.54449816271544
1991	65.0472171842724
1992	63.173698118545
1993	62.99805326480721
1994	66.33192768712254
1995	80.5268206143152
1996	80.50616531582581
1997	90.39205842451476
1998	100
1999	106.97872897378382
2000	121.4718520186799
2001	140.22149714390824
2002	155.23402477575155
2003	168.67569805506466
2004	162.20487914478133