Annual Percent of Total
1960-01-01 45.9298254272424
1961-01-01 46.1386857522870
1962-01-01 46.4080029544211
1963-01-01 46.6765546301039
1964-01-01 46.8518850843024
1965-01-01 46.8975031577295
1966-01-01 46.9372371038445
1967-01-01 46.8697872974913
1968-01-01 46.7343991501292
1969-01-01 46.6038967043945
1970-01-01 46.5193823985038
1971-01-01 46.4986230871753
1972-01-01 46.5379839353334
1973-01-01 46.5926876761930
1974-01-01 46.5860108465324
1975-01-01 46.4755874004571
1976-01-01 46.4526668574675
1977-01-01 46.2423035481182
1978-01-01 45.9194398963239
1979-01-01 45.5807262679939
1980-01-01 45.2604004929523
1981-01-01 44.7458414266526
1982-01-01 44.3231422793472
1983-01-01 43.9159743658155
1984-01-01 43.4217831858165
1985-01-01 42.8044304196961
1986-01-01 42.1116392941583
1987-01-01 41.3430275910533
1988-01-01 40.5357680351495
1989-01-01 39.7588978675699
1990-01-01 39.0501677677680
1991-01-01 38.4183612201428
1992-01-01 37.8111764143661
1993-01-01 37.2401239539056
1994-01-01 36.7079730579428
1995-01-01 36.2115235634840
1996-01-01 35.7581368140098
1997-01-01 35.3575011647356
1998-01-01 34.9908525937930
1999-01-01 34.6293992978844
2000-01-01 34.2554886113328
2001-01-01 33.8726381544103
2002-01-01 33.4794465478080
2003-01-01 33.0795628072515
2004-01-01 32.6837277011706
2005-01-01 32.2958370505675
2006-01-01 31.7983820823636
2007-01-01 31.3021260547980
2008-01-01 30.8040214281650
2009-01-01 30.3022396527368
2010-01-01 29.7998436586638
2011-01-01 29.3118078906648
2012-01-01 28.8402187080218
2013-01-01 28.3802170773220
2014-01-01 27.9251450633384
2015-01-01 27.4723912042319
2016-01-01 27.0801234523113
2017-01-01 26.6675715162257