Year	Percent
1960-01-01	10.2347
1961-01-01	10.0729
1962-01-01	10.1374
1963-01-01	10.0456
1964-01-01	11.2043
1965-01-01	12.3023
1966-01-01	12.8305
1967-01-01	13.4262
1968-01-01	13.2411
1969-01-01	13.1974
1970-01-01	13.6012
1971-01-01	13.3566
1972-01-01	13.3698
1973-01-01	12.6034
1974-01-01	11.8268
1975-01-01	12.5328
1976-01-01	12.2947
1977-01-01	12.1065
1978-01-01	13.9012
1979-01-01	14.9748
1980-01-01	15.8602
1981-01-01	17.3993
1982-01-01	18.3225
1983-01-01	19.6923
1984-01-01	20.4597
1985-01-01	19.4451
1986-01-01	16.0844
1987-01-01	16.0780
1988-01-01	16.5532
1989-01-01	15.6931
1990-01-01	13.4577
1991-01-01	12.1797
1992-01-01	13.4387
1993-01-01	14.2476
1994-01-01	14.8505
1995-01-01	17.6413
1996-01-01	20.0430
1997-01-01	19.6699
1998-01-01	20.3058
1999-01-01	21.7788
2000-01-01	21.6322
2001-01-01	21.3598
2002-01-01	20.9439
2003-01-01	23.0695
2004-01-01	25.2249
2005-01-01	24.8960
2006-01-01	25.6500
2007-01-01	26.4664
2008-01-01	26.6099
2009-01-01	25.6458
2010-01-01	23.8085
2011-01-01	22.7175
2012-01-01	26.8732
2013-01-01	31.2208
2014-01-01	31.7766
2015-01-01	32.4260
2016-01-01	33.3544