Year	years
1960	51.304
1961	51.599
1962	51.886
1963	52.175
1964	52.474
1965	52.709
1966	53.016
1967	53.387
1968	53.716
1969	53.993
1970	54.258
1971	54.681
1972	54.925
1973	55.278
1974	55.589
1975	55.972
1976	56.329
1977	56.67
1978	56.98
1979	57.456
1980	57.6
1981	57.957
1982	58.472
1983	58.76
1984	58.989
1985	59.54
1986	60.047
1987	60.438
1988	60.633
1989	64.2
1990	64.2
1991	64.6
1992	64.2
1993	62.9
1994	61.6
1995	61.4
1996	62.3
1997	62.6
1998	63.1
1999	64.9
2000	64.9
2001	65
2002	64.4
2003	64.5
2004	64.3
2005	64.2
2006	63.5
2007	63.7
2008	64.5
2009	65.2
2010	65.3
2011	65.7
2012	66.1
2013	66.3
2014	66.5
2015	66.7
2016	67
2017	67.2
2018	67.4
2019	67.6
2020	67.8
2021	67.9
2022	68