Year	%
1988	15.32945
1990	24.32455
1991	22.18777
1993	34.13728
1996	21.91439
1997	25.59534
1999	21.96282
2000	22.88025
2001	21.77135
2002	19.42902
2003	19.82824
2004	20.25894
2005	19.96894
2006	17.40471
2007	18.21535
2008	18.13818
2009	16.16527
2010	15.78386
2011	18.16487
2012	16.28984
2013	15.80631
2014	15.72297
2015	14.94578
2016	16.20807
2017	16.49516
2018	14.88162
2019	14.79895
2020	15.9621
2021	15.6382