Year	%
1988	15.3
1990	10.54
1991	10.45
1993	16.29
1996	13.83
1997	10.16
1999	9.48
2000	8.43
2001	8.6
2002	7.69
2003	7.67
2004	7.98
2005	8.06
2006	8.04
2007	7.85
2008	7.8
2009	7.72
2010	7.69
2011	7.68
2012	7.61
2013	7.59
2014	7.56
2015	7.6
2016	7.67
2017	7.82
2018	7.87
2019	10.18
2020	7.82
2021	7.89
