Year	years
1960	44.858
1961	44.972
1962	45.298
1963	45.523
1964	45.724
1965	45.969
1966	46.186
1967	46.397
1968	46.601
1969	46.799
1970	46.987
1971	47.178
1972	47.372
1973	47.563
1974	45.206
1975	45.574
1976	45.963
1977	48.348
1978	48.527
1979	48.731
1980	48.914
1981	49.089
1982	49.257
1983	49.591
1984	49.881
1985	49.679
1986	49.765
1987	50.32
1988	48.542
1989	50.693
1990	51.088
1991	28.415
1992	28.569
1993	52.117
1994	51.784
1995	52.131
1996	51.97
1997	51.623
1998	52.09
1999	51.976
2000	52.066
2001	52.16
2002	52.147
2003	52.106
2004	52.071
2005	52.173
2006	52.212
2007	52.196
2008	52.835
2009	53.446
2010	52.538
2011	53.038
2012	55.139
2013	55.775
2014	56.362
2015	56.93
2016	57.293
2017	57.809
2018	58.545
2019	59.092
2020	58.051
2021	57.414
2022	58.233