Year	years
1960	52.78
1961	53.318
1962	53.828
1963	54.322
1964	54.804
1965	55.284
1966	55.76
1967	56.216
1968	56.673
1969	57.158
1970	57.667
1971	58.183
1972	58.724
1973	59.298
1974	59.89
1975	60.509
1976	61.124
1977	61.768
1978	62.355
1979	62.865
1980	63.357
1981	63.883
1982	64.366
1983	64.838
1984	65.337
1985	65.629
1986	65.785
1987	65.727
1988	65.035
1989	64.846
1990	64.037
1991	63.018
1992	61.862
1993	60.67
1994	59.507
1995	58.225
1996	57.032
1997	55.807
1998	54.662
1999	53.651
2000	52.84
2001	52.448
2002	52.388
2003	52.648
2004	53.276
2005	54.383
2006	55.147
2007	56.99
2008	58.443
2009	60.03
2010	61.829
2011	62.816
2012	62.928
2013	64.637
2014	65.391
2015	66.284
2016	68.059
2017	69.428
2018	67.371
2019	67.891
2020	68.051
2021	63.594
2022	68.399