Year	Percent
1987	25.50515
1988	28.0335
1989	31.13558
1990	33.11399
1991	37.09319
1992	35.13919
1993	27.58509
1994	34.3456
1995	28.04992
1996	22.36476
1997	28.19861
1998	26.8
1999	29.02295
2000	30.0559
2001	29.97381
2002	30.12268
2003	28.46201
2004	26.44401
2005	26.33106
2006	25.07941
2007	23.2359
2008	19.68961
2009	18.63268
2010	26.92203
2011	29.69858
2012	28.96356
2013	27.8106
2014	28.69633
2015	29.22072
2016	29.27665
2017	28.65847
2018	26.56271
2019	24.38182
2020	24.85383
2021	24.61829
2022	23.46539