Year	%
2000	18.546660739143043
2001	18.206779266181623
2002	17.991720564092144
2003	17.87537113984338
2004	17.61167571303867
2005	17.1577716660657
2006	16.884867679184314
2007	16.680855436325164
2008	16.624470566584108
2009	16.40860104901828
2010	16.223125744868494
2011	16.02869292443756
2012	15.839045597147804
2013	15.598087799475795
2014	15.44707837844132
2015	15.402907267331004
2016	15.484838662467466
2017	15.101322201656075
2018	14.930812164718343
2019	14.73931251481255