Year	Percent
1961-01-01	12.16070
1962-01-01	11.60140
1963-01-01	12.43380
1964-01-01	12.94690
1965-01-01	13.86620
1966-01-01	12.35530
1967-01-01	13.47660
1968-01-01	13.15130
1969-01-01	12.22780
1970-01-01	9.63326
1971-01-01	11.10910
1972-01-01	10.82780
1973-01-01	11.13690
1974-01-01	11.70050
1975-01-01	11.34790
1976-01-01	10.88200
1977-01-01	10.91870
1978-01-01	13.32940
1979-01-01	14.20550
1980-01-01	14.47960
1981-01-01	13.98620
1982-01-01	13.76430
1983-01-01	13.23990
1984-01-01	12.80470
1985-01-01	12.98830
1986-01-01	12.27230
1987-01-01	12.47430
1988-01-01	12.48330
1989-01-01	12.66200
1990-01-01	12.49190
1991-01-01	12.99270
1992-01-01	14.67300
1993-01-01	14.22250
1994-01-01	14.16130
1995-01-01	16.26170
1996-01-01	17.39040
1997-01-01	19.50650
1998-01-01	20.94330
1999-01-01	22.40100
2000-01-01	22.99660
2001-01-01	22.21030
2002-01-01	22.38910
2003-01-01	22.17840
2004-01-01	22.42860
2005-01-01	22.79880
2006-01-01	22.08210
2007-01-01	21.29180
2008-01-01	23.76920
2009-01-01	23.44830
2010-01-01	24.61600
2011-01-01	26.95090
2012-01-01	28.10080
2013-01-01	29.22030
2014-01-01	31.18600
2015-01-01	32.00790
2016-01-01	31.34080