Year	years
1960	43.015638094803
1961	43.395855642490226
1962	43.71042067301691
1963	44.035578965430226
1964	44.51702832078211
1965	44.66610037670681
1966	44.578624746593
1967	44.99742105091335
1968	45.42200965710934
1969	45.666024122379966
1970	46.0155059142639
1971	46.52411588552485
1972	46.641245129122666
1973	47.27646337253259
1974	47.481603716626985
1975	47.86693997968956
1976	48.64620120757336
1977	49.17471748092111
1978	49.57450800691291
1979	50.00245350269363
1980	50.36147816803755
1981	50.75817771969595
1982	51.024382330516595
1983	50.17979427706145
1984	50.31086792103257
1985	50.56753703756917
1986	50.97228872305054
1987	51.45543986346641
1988	51.17951724754297
1989	51.91436095368729
1990	51.93862216068479
1991	51.72054745552809
1992	51.52909661874796
1993	51.78047067402533
1994	51.88123399206714
1995	52.01704331711446
1996	51.9253884369714
1997	52.03460216120838
1998	51.81526293291133
1999	52.445727340145766
2000	52.75532892273486
2001	52.937628603626806
2002	53.278864426912094
2003	53.708367215000195
2004	54.168607966418236
2005	54.78910530638715
2006	55.53382813310289
2007	56.214903391891184
2008	56.839127817501215
2009	57.696470539416474
2010	58.35559341163891
2011	59.14174882601448
2012	59.78255972674614
2013	60.39725815333862
2014	60.92525982637781
2015	61.368895092314865
2016	61.88823405279696
2017	62.30683474221162
2018	62.729662038725266
2019	63.13890595089446
2020	62.83038483495726
2021	62.27822957939876
2022	62.77290872255058