Year	%
2000	5.15860873689612
2001	4.7768544168275
2002	4.37072615753459
2003	4.14092993210498
2004	3.98687209817094
2005	3.97471549177851
2006	3.90205207687864
2007	4.05358221305581
2008	4.16262190709203
2009	3.76415364479801
2010	3.72672633601411
2011	3.730390305133
2012	3.79011246046814
2013	3.71741606300524
2014	3.54904808466051
2015	3.38477541585287
2016	3.06584528421282
2017	2.96230331793496
2018	2.88099347899406
2019	2.66561745816842
2020	2.73929434577511