Year	Percent
1980-01-01	6.27055
1981-01-01	48.15190
1982-01-01	73.22670
1983-01-01	62.55550
1984-01-01	56.13240
1985-01-01	52.05240
1986-01-01	49.39550
1987-01-01	45.24150
1988-01-01	32.01130
1989-01-01	18.78960
1990-01-01	14.36340
1991-01-01	18.12680
1992-01-01	17.73740
1993-01-01	16.63490
1994-01-01	14.91640
1995-01-01	14.54700
1996-01-01	16.15330
1997-01-01	18.17700
1998-01-01	20.39300
1999-01-01	22.69010
2000-01-01	24.86610
2001-01-01	26.48630
2002-01-01	26.92110
2003-01-01	27.09270
2004-01-01	26.72800
2005-01-01	27.52180
2006-01-01	29.84460
2007-01-01	34.34590
2008-01-01	42.86680
2009-01-01	47.08230
2010-01-01	46.78880
2011-01-01	48.40810
2012-01-01	50.10700
2013-01-01	50.25380
2014-01-01	50.92960
2015-01-01	51.92630
2016-01-01	52.92150