Year	Units
1964-01-01	1079.29917652298
1965-01-01	1611.06775255937
1967-01-01	1673.24421767167
1968-01-01	1839.14497271430
1969-01-01	1865.51186154113
1970-01-01	2342.73075848951
1971-01-01	2713.68310349946
1972-01-01	2874.71724269802
1973-01-01	3228.16429788080
1974-01-01	2457.27782096860
1975-01-01	4305.64757296942
1976-01-01	5192.75174168032
1977-01-01	7969.62821509532
1978-01-01	9259.28141377393
1979-01-01	6977.63757953610
1980-01-01	3039.16527659318
1981-01-01	3986.19419263777
1982-01-01	6677.21484623649
1983-01-01	5463.82950780076
1984-01-01	6242.70595102413
1985-01-01	7948.92693874368
1986-01-01	6986.20863430626
1987-01-01	5388.14273601687
1988-01-01	5523.46371090497
1989-01-01	7431.68557418212
1990-01-01	9623.33333333334
1991-01-01	13978.08333333330
1992-01-01	16591.16666666670
1993-01-01	12315.75000000000
1994-01-01	9128.66666666666
1995-01-01	10418.58333333330
1996-01-01	11651.75000000000
1997-01-01	13322.25000000000
1998-01-01	15012.08333333330
1999-01-01	21809.25000000000
2000-01-01	24185.16666666670
2001-01-01	23351.16666666670
2002-01-01	22374.08333333330
2003-01-01	21441.08333333330
2004-01-01	24140.91666666670
2005-01-01	22477.33333333330
2006-01-01	22305.75000000000
2007-01-01	23312.08333333330
2008-01-01	22274.58333333330
2009-01-01	18310.83333333330
2010-01-01	11791.75000000000
2011-01-01	8140.00000000000
2012-01-01	4873.25000000000
2013-01-01	4891.33333333333
2014-01-01	5935.16666666667
2015-01-01	6317.00000000000
2016-01-01	6572.75000000000
2017-01-01	7342.91666666667