Year	%
2000	4.37984500422987
2001	4.23419000150094
2002	4.15019328601412
2003	3.97480813653717
2004	3.91506341958859
2005	3.82792713883953
2006	3.696535489298
2007	3.62580645313559
2008	3.59974251903191
2009	3.53065580208209
2010	3.42252309010051
2011	3.25490998731294
2012	3.11882048277732
2013	3.08153274936777
2014	3.00809185177582
2015	2.87472153298521
2016	2.77372356290415
2017	2.73558231014995
2018	2.67538458704644
2019	2.59846907236284
2020	2.46186385289891