Year	years
1960	39.137440572887975
1961	45.04304890495054
1962	53.26807204263749
1963	53.77651577417813
1964	54.51768475666099
1965	54.725231071779206
1966	55.64833617331634
1967	56.48918991453141
1968	56.98607623745958
1969	57.66097169670645
1970	58.401369855404646
1971	59.19662968873727
1972	59.83282528884966
1973	60.80675597941969
1974	61.554790559070995
1975	62.27337827408645
1976	63.079405820976376
1977	63.88661262117093
1978	64.57941038077448
1979	65.20631137613535
1980	65.77148462392906
1981	66.26797085145525
1982	66.76246122272133
1983	67.21671882707564
1984	67.59563902575601
1985	67.97992337176142
1986	68.37172478513108
1987	68.72685725702365
1988	69.03115567730119
1989	69.35446660276679
1990	69.52641842418441
1991	69.56513909480071
1992	70.14355195726667
1993	70.71942269294306
1994	70.90500583031205
1995	71.41650558458117
1996	71.6335482456506
1997	72.02582921133133
1998	72.55706268672732
1999	72.62515836087115
2000	73.06475302582226
2001	73.92405759661926
2002	74.24979890107755
2003	74.64107079860838
2004	74.6599240521933
2005	75.24726392439804
2006	75.60339427146086
2007	75.88139985898694
2008	75.75465883574967
2009	76.39818483701474
2010	76.59777195450675
2011	76.87732991462606
2012	77.15971221538749
2013	77.42462302180778
2014	77.67134245840423
2015	77.91243950218963
2016	78.1567633841824
2017	78.3752143027379
2018	78.69181142846715
2019	78.86308699234556
2020	78.88295962921568
2021	78.47981162224671
2022	78.98680474098099