Year	Percent of Total
1960-01-01	43.1821136077233
1961-01-01	43.6167236704701
1962-01-01	43.7318923586224
1963-01-01	43.6364269763378
1964-01-01	43.4921607411276
1965-01-01	43.3713156203200
1966-01-01	43.1013623255940
1967-01-01	42.9093931474338
1968-01-01	42.7102802377516
1969-01-01	42.3783092606156
1970-01-01	41.8656448255930
1971-01-01	41.2726666476792
1972-01-01	40.5754066014815
1973-01-01	39.8009673420491
1974-01-01	38.9879572928205
1975-01-01	38.1496399178365
1976-01-01	37.3580110808299
1977-01-01	36.4577279194421
1978-01-01	35.5220256339566
1979-01-01	34.6454240238432
1980-01-01	33.8693203523829
1981-01-01	32.9803093603589
1982-01-01	32.2629346512319
1983-01-01	31.6227621516832
1984-01-01	30.9062284516722
1985-01-01	30.0408745035877
1986-01-01	29.2957220835168
1987-01-01	28.3029341246312
1988-01-01	27.1945948763520
1989-01-01	26.1967744145953
1990-01-01	25.4313181393967
1991-01-01	24.5760965884606
1992-01-01	24.0951543878602
1993-01-01	23.8270637009124
1994-01-01	23.5115893417386
1995-01-01	23.0286685832376
1996-01-01	22.8000561483430
1997-01-01	22.2807788063201
1998-01-01	21.6169846932628
1999-01-01	21.0322329846027
2000-01-01	20.6175720110905
2001-01-01	20.1148442635547
2002-01-01	19.7822254639360
2003-01-01	19.5366765160346
2004-01-01	19.2392532298648
2005-01-01	18.8298789018269
2006-01-01	18.3333655446593
2007-01-01	17.8079544329124
2008-01-01	17.2447196950526
2009-01-01	16.6675921574117
2010-01-01	16.1016877836807
2011-01-01	15.6267449737669
2012-01-01	15.1272543431682
2013-01-01	14.6460394996600
2014-01-01	14.2319366897976
2015-01-01	13.9046033078214
2016-01-01	13.6504942843368
2017-01-01	13.4733757727107