Year	years
1960	48.602496560622136
1961	48.9536292160439
1962	49.15240593483608
1963	49.5401175131121
1964	50.048495027358996
1965	50.15678594964683
1966	50.05931918022638
1967	50.47213033470518
1968	50.89440882073532
1969	50.975537113958914
1970	51.23912309499441
1971	51.75209777213727
1972	51.73324207935558
1973	52.30853551350341
1974	52.419689617205705
1975	52.77359552508918
1976	53.24878430585257
1977	53.79801345547094
1978	54.00006526699346
1979	54.223192320178434
1980	54.52034293322698
1981	54.71089932194806
1982	54.80915761656014
1983	54.10933164256176
1984	54.09129670716679
1985	54.191066018322054
1986	54.826875302928926
1987	55.365843836472436
1988	54.97936083079115
1989	55.8226781989144
1990	55.86679373203571
1991	55.731353336531754
1992	55.68024568818603
1993	56.06822034840872
1994	56.53761415601974
1995	56.33551352244685
1996	56.41264268073718
1997	56.692037018399866
1998	56.59083766319699
1999	57.262344280187556
2000	57.6608772612178
2001	57.831907091496205
2002	58.25724240207663
2003	58.56949442357222
2004	58.80921977284143
2005	59.230471533396
2006	59.70180982467208
2007	60.17057821821177
2008	59.99901319661089
2009	61.11531552150398
2010	61.27544320427732
2011	61.97451416233243
2012	62.2283932896497
2013	62.59237740108468
2014	62.8648164920832
2015	63.174735428971644
2016	63.51511695761198
2017	63.89350883162813
2018	64.22686510326301
2019	64.49380590107484
2020	64.04728913232944
2021	63.59176088724828
2022	64.11884367442755