Year	Percent
1976-01-01	10.81374813275930
1977-01-01	11.98928332210510
1978-01-01	9.58437912111289
1981-01-01	14.55821685513700
1982-01-01	9.03577513389664
1983-01-01	10.14534846420070
1984-01-01	8.34693349884503
1985-01-01	9.81036379955918
1986-01-01	8.82034411320076
1987-01-01	7.02175303902782
1988-01-01	8.50786801086302
1989-01-01	11.38713219979580
1990-01-01	14.32097583343040
1991-01-01	15.33478204183400
1992-01-01	10.04591799840880
1993-01-01	11.81969017462570
1994-01-01	22.70564521255180
1995-01-01	14.89950166849880
1996-01-01	9.05641836699616
1997-01-01	7.04733884709026
1998-01-01	6.84567288679074
1999-01-01	4.66140108789280
2000-01-01	5.65826446496309
2001-01-01	6.03482070529730
2002-01-01	6.09421613642327
2003-01-01	5.60347675434471
2004-01-01	4.68840510370265
2005-01-01	4.54036919634532
2006-01-01	4.52668710090664
2007-01-01	5.56072441773021
2008-01-01	9.41346312156962
2009-01-01	3.07546364398805
2010-01-01	3.88627628829636
2011-01-01	5.10765033050847
2012-01-01	3.81733028650700
2013-01-01	2.86639650206209
2014-01-01	2.98130868933673
2015-01-01	1.54869158222488
2016-01-01	1.72826463324536
2017-01-01	3.27955694678546