Annual Percent of Total
1960-01-01 54.2253287574651
1961-01-01 53.5650464076336
1962-01-01 52.9675167785235
1963-01-01 52.4709183718398
1964-01-01 52.0431254572415
1965-01-01 51.6071597354843
1966-01-01 50.9225036286753
1967-01-01 50.1546811427659
1968-01-01 49.3890064432446
1969-01-01 48.7259207511136
1970-01-01 48.2300929784401
1971-01-01 48.2429244292065
1972-01-01 48.4106080747229
1973-01-01 48.7353434687548
1974-01-01 49.1935072175949
1975-01-01 49.7528525642132
1976-01-01 50.7406749599165
1977-01-01 51.6424117223526
1978-01-01 52.4149626911036
1979-01-01 53.0352278108867
1980-01-01 53.5252849570860
1981-01-01 54.0344551263820
1982-01-01 54.4986482962000
1983-01-01 54.9560049717065
1984-01-01 55.4562750899003
1985-01-01 56.0190589565380
1986-01-01 56.3921209965618
1987-01-01 56.8267529785284
1988-01-01 57.2593913435113
1989-01-01 57.5949030618178
1990-01-01 57.7956738642429
1991-01-01 58.1457787795419
1992-01-01 58.3914654318514
1993-01-01 58.5771674658528
1994-01-01 58.7797532001963
1995-01-01 59.0318588813923
1996-01-01 59.2415748208524
1997-01-01 59.4451039826011
1998-01-01 59.6383043823407
1999-01-01 59.8169861117120
2000-01-01 59.9950166813205
2001-01-01 60.3047951614693
2002-01-01 60.6698112297557
2003-01-01 61.0679182499168
2004-01-01 61.4649346575407
2005-01-01 61.8470761362100
2006-01-01 62.3834764529238
2007-01-01 62.8845163714791
2008-01-01 63.3969052249328
2009-01-01 63.9674232065966
2010-01-01 64.5942262025195
2011-01-01 65.1100391483563
2012-01-01 65.7056760455503
2013-01-01 66.3247898613055
2014-01-01 66.8610003818892
2015-01-01 67.2429449980396
2016-01-01 67.5307624364231
2017-01-01 67.5891663803641