Year	Percent
1973-01-01	29.35340000000000
1974-01-01	28.30070000000000
1975-01-01	31.28660000000000
1976-01-01	33.54120000000000
1977-01-01	37.86660000000000
1978-01-01	39.25490000000000
1979-01-01	42.39870000000000
1980-01-01	45.99820000000000
1981-01-01	55.66680000000000
1982-01-01	76.14460000000000
1983-01-01	100.39200000000001
1984-01-01	104.58200000000001
1985-01-01	106.91600000000000
1986-01-01	107.79500000000000
1987-01-01	47.66780000000000
1988-01-01	43.80980000000000
1989-01-01	29.14050000000000
1990-01-01	32.09750000000000
1991-01-01	20.74010000000000
1992-01-01	26.71910000000000
1993-01-01	36.80640000000000
1994-01-01	28.37180000000000
1995-01-01	26.84670000000000
1996-01-01	32.76280000000000
1997-01-01	39.19630000000000
1998-01-01	44.29760000000000
1999-01-01	41.08410000000000
2000-01-01	42.01630000000000
2001-01-01	44.80630000000000
2002-01-01	46.72110000000000
2003-01-01	46.77320000000000
2004-01-01	45.02680000000000
2005-01-01	45.73150000000000
2006-01-01	45.54060000000000
2007-01-01	42.73370000000000
2008-01-01	42.04650000000000
2009-01-01	44.07790000000000
2010-01-01	43.92990000000000
2011-01-01	45.10560000000000
2012-01-01	45.40850000000000
2013-01-01	47.53220000000000
2014-01-01	48.70170000000000
2015-01-01	48.41000000000000
2016-01-01	47.10340000000000