Year	years
1960	42.67512055440581
1961	43.29049127667166
1962	44.25814700887555
1963	44.850945629525576
1964	45.40044742449053
1965	45.92442188837533
1966	46.63657975740033
1967	46.49409218931869
1968	47.32819118730068
1969	47.88132381357628
1970	48.85883323886801
1971	46.91478037339721
1972	49.84870607781685
1973	50.30108280016654
1974	50.60064716773293
1975	51.04745265778535
1976	51.40226302321606
1977	51.62507480961507
1978	51.880713437967586
1979	52.15636552415649
1980	52.678549687161144
1981	53.12282244727848
1982	53.301311064817604
1983	53.61126470409687
1984	53.775754723394705
1985	53.93035643653212
1986	54.012573106990594
1987	53.88144218496201
1988	53.87189032690112
1989	53.95865270639337
1990	53.938769714919964
1991	53.869001999934326
1992	53.818796234382575
1993	53.69842264432993
1994	53.58036248104295
1995	53.32747681930452
1996	53.42575955354307
1997	53.415050955949994
1998	53.739626756383146
1999	54.162734450011115
2000	54.66830728578547
2001	54.93512957239661
2002	55.30251941826142
2003	55.600120989538304
2004	55.83913493670039
2005	55.85315448839815
2006	56.53087715404998
2007	56.68783658285608
2008	56.9427414216281
2009	57.27148715458652
2010	57.614396716187684
2011	57.975024023269455
2012	58.17411957535634
2013	58.45164318408882
2014	58.596082172920795
2015	58.819977935032284
2016	59.10365716780942
2017	59.31610648240201
2018	59.5433356691015
2019	59.83968067676117
2020	59.36505707703146
2021	59.041290943201375
2022	59.6664195320413