Year	years
1960	52.529506448410324
1961	53.08199778004288
1962	53.52361034332125
1963	53.959499272970874
1964	54.44273161457083
1965	54.796920146391436
1966	55.226926820557004
1967	55.60055911046085
1968	55.95633591430313
1969	56.29663590213624
1970	56.38564007264053
1971	57.14655292068902
1972	57.473467713239934
1973	57.9807577799233
1974	58.3992873285246
1975	58.868813376871316
1976	59.07197673015165
1977	59.544202925774506
1978	59.85628494675243
1979	60.17090169191915
1980	60.6002897854032
1981	61.051718004553216
1982	61.35552018774127
1983	61.9441117962698
1984	62.35171271851886
1985	62.733388401106374
1986	63.300256683698116
1987	63.6982197064514
1988	64.10433487534937
1989	64.38171547638107
1990	64.57359074686445
1991	64.91799898680968
1992	65.24273675859304
1993	65.56361975196376
1994	65.97389180593599
1995	66.25399684835875
1996	66.6364457070819
1997	66.99014921068523
1998	67.270808706811
1999	67.66619184199416
2000	67.87021986957599
2001	68.11137393333043
2002	68.48270700071589
2003	68.74204191844927
2004	69.05723892639418
2005	69.4643021408707
2006	69.6770677107727
2007	69.82335732759017
2008	70.06018756606638
2009	70.2867922745201
2010	70.19102338558599
2011	70.68555801920624
2012	70.89628517756698
2013	71.19892983664307
2014	71.4423825044271
2015	71.46254583198673
2016	71.36376100945489
2017	71.60074299140199
2018	71.7009995505624
2019	71.88152100636908
2020	69.55179099859973
2021	68.7226452749016
2022	70.53331902918823