Year	Percent
1971	879.40326
1972	1498.77781
1973	2672.35283
1974	6081.72218
1975	5461.16873
1976	6517.14507
1977	5809.29425
1978	2119.98678
1979	2253.12839
1980	1376.58479
1981	834.38767
1982	940.35482
1983	589.0722
1984	405.71251
1985	466.82608
1986	472.3633
1987	501.63155
1988	479.322
1989	449.62361
1990	235.60556
1991	290.31057
1992	251.91002
1993	433.38926
1994	348.81701
1995	272.33969
1996	232.40887
1997	169.90923
1998	132.09706
1999	123.10344
2000	84.13003
2001	55.85453
2002	59.51245
2003	86.10946
2004	69.33593
2005	73.13731
2006	79.71771
2007	79.81708
2008	116.47558
2009	158.38932
2010	180.24202
2011	192.77844
2012	180.30233
2013	154.78467
2014	169.21974
2015	157.07997
2016	168.66181