Year	%
1988	19.02
1989	13.76
1990	13.81
1992	13
1995	11.43
1996	21
1997	20.31
1998	21.82
1999	11.12
2000	21.47
2001	22.43
2002	21.08
2003	21.93
2004	21.25
2005	21.52
2006	21.61
2007	20.73
2008	24.7
2009	24.89
2010	25.61
2011	26.58
2012	26.05
2013	27.25
2014	21.68
2015	24
2016	31.29
2017	21.21
2018	20.61
2020	21.11
2021	20.58