Year	Percent
1960-01-01	1.255230125529260
1961-01-01	3.451628585578260
1962-01-01	7.377819548184620
1963-01-01	6.105032823029300
1964-01-01	3.092783505154520
1965-01-01	5.449999999250480
1966-01-01	7.064959696588140
1967-01-01	8.207853558440210
1968-01-01	8.005207103664560
1969-01-01	3.487919243952040
1970-01-01	6.514841416529830
1971-01-01	5.869869590719010
1972-01-01	6.562360902565460
1973-01-01	9.303382979736680
1974-01-01	15.275206221839400
1975-01-01	9.605612075386740
1976-01-01	9.010290835622270
1977-01-01	10.922237810032900
1978-01-01	10.213654571040500
1979-01-01	9.611050379071190
1980-01-01	12.305324076018200
1981-01-01	11.767387434418200
1982-01-01	10.120825677982300
1983-01-01	6.908228811588470
1984-01-01	6.290779360237670
1985-01-01	4.678751451832500
1986-01-01	3.678184118634580
1987-01-01	4.019993456831550
1988-01-01	4.535133010157260
1989-01-01	4.772723424355240
1990-01-01	2.641603063820000
1991-01-01	2.395153317244140
1992-01-01	2.096044429332130
1993-01-01	1.257856679532610
1994-01-01	1.992014638095230
1995-01-01	2.083608423828500
1996-01-01	2.126298022755790
1997-01-01	2.182166779071170
1998-01-01	1.845651220078910
1999-01-01	2.497795444045280
2000-01-01	2.903282032364570
2001-01-01	2.337870002552610
2002-01-01	2.424436612196940
2003-01-01	2.075078206465040
2004-01-01	1.154356931249370
2005-01-01	1.817814582912570
2006-01-01	1.924221384645880
2007-01-01	1.693265862203190
2008-01-01	3.416267942583750
2009-01-01	1.304709910243360
2010-01-01	2.310924369747890
2011-01-01	2.758682260512460
2012-01-01	2.397914856646390
2013-01-01	0.789071780078061
2014-01-01	0.564020540449518
2015-01-01	0.452034153691623
2016-01-01	0.249999999999997
2017-01-01	1.147132169576060