Year	Percent
1976	98.39062
1977	100.64085
1978	105.42016
1979	99.57807
1980	98.43286
1981	93.94874
1982	93.63401
1983	94.75538
1984	103.54263
1985	114.34657
1986	104.51481
1987	97.61494
1988	90.00496
1989	83.71074
1990	82.46225
1997	97.24629
1998	98.43559
1999	94.89542
2000	95.63971
2001	97.61189
2002	98.96029
2003	95.68278
2004	94.87549
2005	93.33555
2006	98.49866
2007	94.36687
2008	95.41519
2009	96.62655
2010	96.54704
2011	98.98783
2012	97.36932
2013	98.04022
2014	96.38021
2015	96.90144
2016	98.38153