Year	years
1960	47.949
1961	48.697
1962	49.485
1963	49.93
1964	50.436
1965	50.923
1966	51.085
1967	51.667
1968	51.94
1969	52.288
1970	52.427
1971	50.6
1972	50.619
1973	49.855
1974	50.169
1975	49.236
1976	48.793
1977	48.442
1978	48.783
1979	48.482
1980	47.392
1981	47.421
1982	48.142
1983	48.433
1984	48.601
1985	49.763
1986	49.622
1987	49.611
1988	49.608
1989	49.29
1990	48.992
1991	48.789
1992	48.695
1993	48.381
1994	48.637
1995	48.85
1996	49.099
1997	49.299
1998	49.601
1999	50.186
2000	50.62
2001	51.093
2002	51.578
2003	51.913
2004	52.832
2005	54.269
2006	55.885
2007	56.719
2008	57.337
2009	58.183
2010	58.768
2011	59.722
2012	60.76
2013	61.848
2014	62.259
2015	63.005
2016	63.809
2017	64.028
2018	64.744
2019	64.99
2020	64.898
2021	64.92
2022	65.703