Year	years
1960	52.034
1961	52.794
1962	53.765
1963	54.642
1964	55.775
1965	56.894
1966	58.184
1967	59.421
1968	60.539
1969	61.829
1970	63.121
1971	64.31
1972	65.185
1973	66.47
1974	67.239
1975	68.035
1976	68.816
1977	69.535
1978	70.28
1979	70.965
1980	71.67
1981	72.006
1982	72.604
1983	72.876
1984	73.412
1985	73.64
1986	73.775
1987	74.513
1988	74.648
1989	74.788
1990	74.922
1991	75.04
1992	74.99
1993	75.524
1994	75.595
1995	75.633
1996	75.343
1997	75.534
1998	75.676
1999	76.193
2000	76.617
2001	76.998
2002	77.35
2003	78.521
2004	78.784
2005	79.033
2006	79.289
2007	79.52
2008	79.75
2009	79.982
2010	80.203
2011	80.415
2012	80.623
2013	80.828
2014	81.023
2015	81.212
2016	81.396
2017	81.626
2018	81.79
2019	81.907
2020	81.112
2021	80.937
2022	81.412