Annual Percent of Total
1960-01-01 3.93907884274268
1961-01-01 3.90672461329969
1962-01-01 3.85741096563743
1963-01-01 3.80760023937762
1964-01-01 3.76297931485569
1965-01-01 3.72662924090798
1966-01-01 3.67046852286705
1967-01-01 3.62508222660764
1968-01-01 3.59728698601102
1969-01-01 3.58098873460409
1970-01-01 3.57068442619788
1971-01-01 3.55716664456331
1972-01-01 3.53691412161354
1973-01-01 3.51777059773829
1974-01-01 3.51430284509603
1975-01-01 3.52258599254041
1976-01-01 3.43054498763553
1977-01-01 3.32431210770543
1978-01-01 3.19766960724275
1979-01-01 3.04440039220702
1980-01-01 2.86054581359017
1981-01-01 2.85878501636804
1982-01-01 2.85259644492742
1983-01-01 2.83874495606592
1984-01-01 2.82687293506303
1985-01-01 2.82301168757127
1986-01-01 2.80250419964325
1987-01-01 2.77836227285352
1988-01-01 2.74689312683569
1989-01-01 2.70243405933666
1990-01-01 2.64273431613115
1991-01-01 2.63525541359652
1992-01-01 2.62736208904122
1993-01-01 2.62430301933267
1994-01-01 2.63258785942492
1995-01-01 2.65585883873052
1996-01-01 2.59863012349893
1997-01-01 2.54488235407226
1998-01-01 2.49606856670280
1999-01-01 2.44874942152509
2000-01-01 2.39856440233945
2001-01-01 2.51854508889588
2002-01-01 2.63184448217905
2003-01-01 2.73947406399180
2004-01-01 2.85072165063153
2005-01-01 2.97323350440083
2006-01-01 3.09844699527346
2007-01-01 3.20783003969440
2008-01-01 3.29437946273190
2009-01-01 3.35876510011152
2010-01-01 3.40218493189455
2011-01-01 3.49430094946106
2012-01-01 3.60026816894644
2013-01-01 3.72896311705725
2014-01-01 3.89187377339059
2015-01-01 4.09515689439625
2016-01-01 4.32447376629269
2017-01-01 4.59065493810314