Year	Percent
1960-01-01	7.965578038872300
1961-01-01	8.195648958306650
1962-01-01	6.618317755724710
1963-01-01	20.691629062131800
1964-01-01	29.462815679637900
1965-01-01	13.548203286359800
1966-01-01	11.261385850285300
1967-01-01	10.882442152475500
1968-01-01	10.771819576674100
1969-01-01	12.389567678959800
1970-01-01	15.950341614600100
1971-01-01	13.511703854677900
1972-01-01	11.688985710263300
1973-01-01	3.221029138701310
1974-01-01	24.304195373693700
1975-01-01	25.249257899194400
1976-01-01	15.327328537380600
1977-01-01	10.096663159066900
1978-01-01	14.460287622011600
1979-01-01	18.323500304200700
1980-01-01	28.697587276634000
1981-01-01	21.351653170103900
1982-01-01	7.190847625697210
1983-01-01	3.420615454014780
1984-01-01	2.273942298416020
1985-01-01	2.459117006093900
1986-01-01	2.749983269532850
1987-01-01	3.049659098141690
1988-01-01	7.146095256312110
1989-01-01	5.700160936700560
1990-01-01	8.573600687098220
1991-01-01	9.333360724777630
1992-01-01	6.212678644574800
1993-01-01	4.801102489801260
1994-01-01	6.265814771988770
1995-01-01	4.480686995253550
1996-01-01	4.924809686634800
1997-01-01	4.439063761097680
1998-01-01	7.513340122482140
1999-01-01	0.812996589285747
2000-01-01	2.259184778504150
2001-01-01	4.066419647998390
2002-01-01	2.762511352086060
2003-01-01	3.514879241868620
2004-01-01	3.590591390858020
2005-01-01	2.754090200547540
2006-01-01	2.241847104391480
2007-01-01	2.534846871184780
2008-01-01	4.673795956916200
2009-01-01	2.756686477375810
2010-01-01	2.939181359275980
2011-01-01	4.025846249593850
2012-01-01	2.187221208479320
2013-01-01	1.301377057536110
2014-01-01	1.274714702055190
2015-01-01	0.706208169859214
2016-01-01	0.971674763956376
2017-01-01	1.944455907233950