Year	% of population
2001	2.9012556707137103
2002	2.8080941411475164
2003	2.751340235327052
2004	2.719521861632414
2005	2.718313421930809
2006	2.713443165676803
2007	2.7215684264470315
2008	2.735294533001971
2009	2.774410851266345
2010	2.8144065044218745
2011	2.792812421160194
2012	2.75444669782629
2013	2.7088911910080196
2014	2.6865345716426416
2015	2.663795176400608
2016	2.6562706405224397
2017	2.6433625939989813
2018	2.6298044429106358
2019	2.6097322545894728
2020	2.604709727769646
2021	2.632759123120971