Year	Percent of Total
1960-01-01	2.98709537100808
1961-01-01	3.01810972047655
1962-01-01	3.04755849791992
1963-01-01	3.07396280713933
1964-01-01	3.09367748038634
1965-01-01	3.10715525696430
1966-01-01	3.13830309204163
1967-01-01	3.16033927216153
1968-01-01	3.17423414170457
1969-01-01	3.18042027899675
1970-01-01	3.18076070799003
1971-01-01	3.17167641557172
1972-01-01	3.15604540542490
1973-01-01	3.13274869236460
1974-01-01	3.10137918256234
1975-01-01	3.05993805297695
1976-01-01	3.00645109813152
1977-01-01	2.94229541995975
1978-01-01	2.87228892331526
1979-01-01	2.79982744929949
1980-01-01	2.72683408135456
1981-01-01	2.66543884213088
1982-01-01	2.60442706092732
1983-01-01	2.54309575291107
1984-01-01	2.48029980217696
1985-01-01	2.41795174507497
1986-01-01	2.38857022069774
1987-01-01	2.35890173496047
1988-01-01	2.33100691489742
1989-01-01	2.30627857290542
1990-01-01	2.28627714992054
1991-01-01	2.24150649682565
1992-01-01	2.19596153235277
1993-01-01	2.15128436652284
1994-01-01	2.10935623628067
1995-01-01	2.07133113125674
1996-01-01	2.13478454091939
1997-01-01	2.20244442439304
1998-01-01	2.27374965306689
1999-01-01	2.34953111376999
2000-01-01	2.43254933551324
2001-01-01	2.47691833708314
2002-01-01	2.51541692638217
2003-01-01	2.54664595609274
2004-01-01	2.57044582454410
2005-01-01	2.58741695931419
2006-01-01	2.61835987814127
2007-01-01	2.65611421523966
2008-01-01	2.68878664624391
2009-01-01	2.70130304390446
2010-01-01	2.68864295437060
2011-01-01	2.59116637856365
2012-01-01	2.49125162642973
2013-01-01	2.40276051527679
2014-01-01	2.34215492593271
2015-01-01	2.31436660229868
2016-01-01	2.32600081089107
2017-01-01	2.35504378311666