Year	Percent
1980-01-01	8.14883000000000000
1981-01-01	7.13340000000000000
1982-01-01	5.59261000000000000
1983-01-01	5.30194000000000000
1984-01-01	4.56036000000000000
1985-01-01	4.21648000000000100
1986-01-01	4.40599000000000000
1987-01-01	4.77705000000000000
1988-01-01	3.61244000000000030
1989-01-01	3.26583000000000000
1990-01-01	2.38516000000000000
1991-01-01	2.33393000000000000
1992-01-01	2.05666000000000000
1993-01-01	1.49918000000000000
1994-01-01	0.10902000000000000
1995-01-01	0.10680899999999999
1996-01-01	32.18400000000000000
1997-01-01	41.54640000000000000
1998-01-01	35.35730000000000000
1999-01-01	37.75380000000000000
2000-01-01	40.12450000000000000
2001-01-01	41.27740000000000000
2002-01-01	37.42210000000000000
2003-01-01	36.57480000000000000
2004-01-01	37.95230000000000000
2005-01-01	41.92070000000000000
2006-01-01	41.78470000000000000
2007-01-01	37.51510000000000000
2008-01-01	31.19030000000000000
2009-01-01	33.84630000000000000
2010-01-01	30.70060000000000000
2011-01-01	26.03590000000000000
2012-01-01	21.43340000000000000
2013-01-01	21.71080000000000000
2014-01-01	22.58199999999999700
2015-01-01	21.70510000000000000
2016-01-01	22.18070000000000000