Year	years
1960	42.26452621571935
1961	42.748886293459165
1962	43.21249090277478
1963	43.35027045075129
1964	44.10161451946542
1965	44.06192037945059
1966	44.418321232757854
1967	45.06232939292441
1968	45.42889174796133
1969	45.678138166690005
1970	44.35236019814644
1971	42.97265025868614
1972	46.285417907311505
1973	46.82155289860669
1974	46.72379919901134
1975	46.54712634681521
1976	47.10077507520165
1977	47.921733406149976
1978	48.372491016081995
1979	48.8625921099779
1980	49.319924498222406
1981	49.64068179358119
1982	49.99795636740946
1983	49.265175019222525
1984	49.511848965584925
1985	49.88178988877631
1986	50.53645576148261
1987	51.175758461101466
1988	50.97835061720312
1989	51.763001579028526
1990	52.02494396745469
1991	51.67587596147155
1992	52.430377059068526
1993	52.98317263543773
1994	53.55896138418807
1995	54.08425867484262
1996	54.17466685672122
1997	55.007485620096304
1998	55.5271729122385
1999	56.66311315527114
2000	57.10266281039178
2001	57.62907347178195
2002	58.189512645415086
2003	58.8342469799439
2004	59.29930215615459
2005	59.9202694578291
2006	60.51951626969977
2007	60.99414674024502
2008	61.09379688452093
2009	62.21097717336623
2010	62.720209938098115
2011	63.52112580868453
2012	64.24827239435835
2013	64.90544124478815
2014	65.26549655164455
2015	65.67111577162456
2016	66.24451098179414
2017	66.63073546880968
2018	67.06975790265267
2019	67.49545408998614
2020	66.95964726172392
2021	66.62249551146067
2022	67.38949363586256