Year	%
2000	22.905587451075263
2001	22.620787311561454
2002	22.506921798145022
2003	22.299634954115948
2004	21.842210167313965
2005	21.561097870062174
2006	21.124234274395207
2007	20.834567887268424
2008	20.6624512984308
2009	20.415231788355673
2010	20.26793046805439
2011	20.02738457712789
2012	19.76871758471146
2013	19.31315369449292
2014	19.04564480915523
2015	18.98458377029949
2016	18.900193088585596
2017	18.602137188346962
2018	18.426205087011184
2019	18.285180139193617