Year	Percent
1981	142.36567
1982	155.55334
1983	149.67243
1984	142.12447
1985	132.08898
1986	138.98145
1987	107.94023
1988	98.50914
1989	81.52205
1990	78.25517
1991	78.31256
1992	69.98856
1993	77.47869
1994	82.07761
1995	58.44773
1996	52.74919
1997	56.38228
1998	73.84885
1999	73.66834
2000	66.76333
2001	80.17275
2002	65.20764
2003	62.96086
2004	68.48212
2005	72.25011
2006	76.4632
2007	80.05224
2008	80.44271
2009	93.72249
2010	50.00408
2011	48.79582
2012	50.01433
2013	52.3666
2014	54.15313
2015	58.12222
2016	59.7851
2017	55.8011