Year	years
1960	47.096
1961	47.325
1962	47.405
1963	47.578
1964	47.719
1965	47.778
1966	47.727
1967	47.683
1968	47.57
1969	47.565
1970	47.805
1971	47.798
1972	48.026
1973	48.398
1974	48.777
1975	49.246
1976	49.764
1977	50.085
1978	50.571
1979	50.932
1980	51.117
1981	51.269
1982	51.383
1983	51.622
1984	52.051
1985	52.416
1986	53.125
1987	53.824
1988	54.507
1989	55.191
1990	55.62
1991	56.012
1992	56.231
1993	56.416
1994	56.112
1995	56.565
1996	56.82
1997	57.199
1998	57.6
1999	58.03
2000	58.195
2001	58.107
2002	58.608
2003	59.111
2004	59.191
2005	59.76
2006	59.988
2007	60.224
2008	60.49
2009	60.946
2010	61.157
2011	61.652
2012	62.081
2013	62.42
2014	63.045
2015	63.175
2016	63.89
2017	64.013
2018	64.122
2019	64.74
2020	64.114
2021	63.795
2022	63.945