Annual Percent of Total
1960-01-01 50.5746002780674
1961-01-01 49.9149974129648
1962-01-01 49.4680851063830
1963-01-01 49.1294277385089
1964-01-01 48.8614423347466
1965-01-01 48.6519850356675
1966-01-01 48.5463707280492
1967-01-01 48.4550811060235
1968-01-01 48.4133343672724
1969-01-01 48.4567461282398
1970-01-01 48.5906270972811
1971-01-01 48.2991834477895
1972-01-01 48.0684231222965
1973-01-01 47.9055485946757
1974-01-01 47.8146633462039
1975-01-01 47.7952874080744
1976-01-01 47.8501187595729
1977-01-01 48.0221039645519
1978-01-01 48.3222394128018
1979-01-01 48.6628215562082
1980-01-01 48.9563317262669
1981-01-01 49.5486765244026
1982-01-01 49.9676567656766
1983-01-01 50.2830152353326
1984-01-01 50.6189701085770
1985-01-01 51.0401950024557
1986-01-01 51.1924419701830
1987-01-01 51.4806103717302
1988-01-01 51.8265299282794
1989-01-01 52.1434138737335
1990-01-01 52.4099982938065
1991-01-01 52.5328840660088
1992-01-01 52.5702846379884
1993-01-01 52.5974617439883
1994-01-01 52.6775885835557
1995-01-01 52.8181365751366
1996-01-01 53.3971994983059
1997-01-01 54.0206492603991
1998-01-01 54.5760886557468
1999-01-01 55.0086601457582
2000-01-01 55.3508683258193
2001-01-01 55.7678128823769
2002-01-01 56.1806365987049
2003-01-01 56.6265373611266
2004-01-01 57.1275929138792
2005-01-01 57.6862929217692
2006-01-01 58.2595865133604
2007-01-01 58.8414480893545
2008-01-01 59.4186141459670
2009-01-01 59.9718407665428
2010-01-01 60.4885450610682
2011-01-01 61.2183771173054
2012-01-01 61.8830950903027
2013-01-01 62.5182680043349
2014-01-01 63.1520583234289
2015-01-01 63.7833715570795
2016-01-01 64.2423846040648
2017-01-01 64.7265273659460