Year	Percent
1974-01-01	15.407400000000000
1975-01-01	12.894700000000000
1976-01-01	15.317800000000000
1977-01-01	17.172400000000000
1978-01-01	19.048100000000000
1979-01-01	18.776400000000000
1980-01-01	15.995600000000000
1981-01-01	13.218500000000000
1982-01-01	13.675000000000000
1983-01-01	16.784000000000002
1984-01-01	17.175700000000000
1985-01-01	18.704200000000000
1986-01-01	22.385300000000000
1987-01-01	22.576900000000000
1988-01-01	23.729600000000000
1989-01-01	36.245100000000000
1990-01-01	36.245100000000000
1991-01-01	101.880000000000000
1992-01-01	174.194000000000020
1993-01-01	351.180000000000000
1994-01-01	562.518000000000000
1995-01-01	668.096000000000000
1996-01-01	599.752000000000000
1997-01-01	307.989000000000030
1998-01-01	394.441000000000000
1999-01-01	457.330000000000000
2000-01-01	428.760999999999970
2001-01-01	444.657000000000000
2002-01-01	459.544000000000040
2003-01-01	628.624000000000000
2004-01-01	680.737000000000000
2005-01-01	828.363999999999900
2006-01-01	981.911999999999900
2007-01-01	22.708300000000000
2008-01-01	29.032900000000000
2009-01-01	27.743500000000000
2010-01-01	31.792900000000000
2011-01-01	35.164700000000000
2012-01-01	34.989300000000000
2013-01-01	33.913300000000000