Year	years
1960	45.83324662687874
1961	48.67189597024423
1962	52.36202751901587
1963	52.83525926988653
1964	53.357198145382355
1965	53.06447912103443
1966	53.75525350994389
1967	54.24372862893578
1968	54.941076864376704
1969	55.34945160119888
1970	55.893028823461414
1971	56.52367017080218
1972	56.9758743902748
1973	57.64069109961138
1974	58.19892297502896
1975	58.802518778225014
1976	59.348282165047934
1977	59.90530817268636
1978	60.38354631354621
1979	60.88224540806113
1980	61.31522544996308
1981	61.76018217977518
1982	62.22059245525456
1983	62.67138979871408
1984	63.075013845329416
1985	63.492980224538606
1986	63.987792266120024
1987	64.34350197438427
1988	64.64476355671151
1989	64.98910233537657
1990	65.19617471350588
1991	65.47576456418953
1992	65.77280751823491
1993	66.02508130016791
1994	66.29489911642725
1995	66.63462504952452
1996	66.95908807253669
1997	67.33296498630301
1998	67.69832114157201
1999	67.90643222193398
2000	68.24743512533219
2001	68.66085954407701
2002	68.994274429816
2003	69.26349822912515
2004	69.50828163420807
2005	69.93085116119661
2006	70.28729754429338
2007	70.57869012943061
2008	70.79632495438065
2009	71.17416880579978
2010	71.45871278921238
2011	71.80122803287003
2012	72.14771627610502
2013	72.49727879666618
2014	72.85412587900008
2015	73.15400075842608
2016	73.42130804393739
2017	73.64321077190874
2018	73.93598110805621
2019	74.13222835710869
2020	73.38233848137897
2021	72.14185295009452
2022	72.93504645909029