Year	years
1961	72.00658536585365
1962	72.11219512195122
1966	72.28560975609756
1967	71.509756097561
1968	71.05658536585366
1969	70.97048780487806
1970	71.21341463414635
1971	71.7190243902439
1972	71.07804878048782
1973	71.69341463414635
1974	71.66170731707318
1975	72.04512195121951
1976	72.95609756097562
1977	72.95853658536586
1978	73.20731707317073
1979	73.50731707317074
1980	73.87560975609756
1981	74.26097560975612
1982	74.10975609756099
1983	74.45853658536585
1984	74.80731707317074
1985	75.20731707317074
1986	74.95609756097562
1987	75.25853658536586
1988	74.43658536585367
1989	76.30731707317074
1990	76.60731707317075
1991	76.75853658536587
1992	76.5048780487805
1993	77.15365853658537
1994	77.40243902439026
1995	77.45121951219514
1996	78.1048780487805
1997	78
1998	78.14878048780487
1999	78.65853658536587
2000	78.95365853658538
2001	79.40731707317074
2002	79.45121951219512
2003	79.64878048780488
2004	80.14634146341464
2005	80.15121951219513
2006	80.55365853658537
2007	80.50487804878051
2008	80.95121951219512
2009	81.40487804878049
2010	81.60243902439025
2011	81.65609756097562
2012	81.7048780487805
2013	82.05609756097562
2014	82.15365853658537
2015	82.05121951219512
2016	82.40731707317074
2017	82.55121951219512
2018	82.80243902439025
2019	82.8048780487805
2020	82.64878048780488
2021	82.50000000000001
2022	82.70000000000002