Year	%
1988	6.067648
1993	4.883753
1995	23.09698
1996	23.97025
1997	25.5273
1998	31.42183
1999	22.58488
2000	30.5969
2001	24.94543
2002	26.46147
2003	24.13496
2004	24.18223
2005	24.15944
2006	23.37983
2007	24.00429
2008	23.66015
2009	23.24535
2010	30.36781
2011	30.51722
2012	31.16851
2013	30.87657
2014	26.72702
2015	31.40135
2016	31.39577
2017	31.23266
2018	30.63676
2019	24.39475
2020	25.06034
2021	25.20465