Year	years
1960	35.26
1961	35.501
1962	35.651
1963	35.837
1964	36.039
1965	36.276
1966	36.581
1967	36.829
1968	37.202
1969	37.374
1970	37.655
1971	37.964
1972	38.304
1973	38.616
1974	38.856
1975	39.272
1976	39.735
1977	40.034
1978	40.489
1979	40.957
1980	41.431
1981	41.883
1982	42.608
1983	43.061
1984	43.756
1985	44.334
1986	44.876
1987	45.429
1988	45.772
1989	46.156
1990	46.449
1991	46.853
1992	47.523
1993	48.123
1994	48.358
1995	49.127
1996	49.88
1997	50.644
1998	51.578
1999	51.921
2000	52.096
2001	52.174
2002	52.878
2003	53.23
2004	53.535
2005	53.919
2006	54.302
2007	54.587
2008	54.97
2009	55.313
2010	55.518
2011	55.851
2012	55.995
2013	56.489
2014	56.434
2015	56.874
2016	57.761
2017	57.926
2018	58.326
2019	58.544
2020	58.113
2021	57.595
2022	57.643