Year	%
1998	6.42
1999	5.88
2000	7.22
2001	10.37
2002	10.76
2003	14.58
2004	14.38
2005	14.1
2006	13.23
2007	16.01
2015	17.69
2016	17.57
2017	15.83
2018	18.11