Year	Percent
1960-01-01	3.728813559322050
1961-01-01	2.287581699346400
1962-01-01	-0.319488817891384
1963-01-01	0.641025641025639
1964-01-01	2.866242038216560
1965-01-01	3.405572755417980
1966-01-01	3.293413173652690
1967-01-01	3.478260869565210
1968-01-01	2.521008403361330
1969-01-01	3.278688524590170
1970-01-01	3.439153439153440
1971-01-01	6.138107416879790
1972-01-01	6.024096385542180
1973-01-01	9.090909090909110
1974-01-01	15.416666666666700
1975-01-01	15.162454873646200
1976-01-01	13.322884012539200
1977-01-01	12.309820193637600
1978-01-01	8.004926108374370
1979-01-01	9.122006841505120
1980-01-01	10.135841170323900
1981-01-01	9.487666034155610
1982-01-01	11.351819757365700
1983-01-01	10.038910505836600
1984-01-01	3.960396039603950
1985-01-01	6.734693877551010
1986-01-01	9.050350541746350
1987-01-01	8.533021624780830
1988-01-01	7.215939687668260
1989-01-01	7.533902561526920
1990-01-01	7.333021952358690
1991-01-01	3.176675369886860
1992-01-01	1.012231126107110
1993-01-01	1.753653444676410
1994-01-01	1.969634796881420
1995-01-01	4.627766599597580
1996-01-01	2.615384615384620
1997-01-01	0.224887556221881
1998-01-01	0.860134629768157
1999-01-01	1.483129403040380
2000-01-01	4.457435147972250
2001-01-01	4.407135362014700
2002-01-01	2.981574539363490
2003-01-01	2.732595966167830
2004-01-01	2.343255224825870
2005-01-01	2.691831683168310
2006-01-01	3.555287737270280
2007-01-01	2.327611288914760
2008-01-01	4.350298549900470
2009-01-01	1.771117166212520
2010-01-01	2.918340026773760
2011-01-01	3.303850156087440
2012-01-01	1.762780156131930
2013-01-01	2.449888641425390
2014-01-01	2.487922705314030
2015-01-01	1.508366721659210
2016-01-01	1.276990944973280
2017-01-01	1.948647409445220