Year	%
2000	21.114767664840294
2001	20.78139134284316
2002	20.51373883422331
2003	20.416311728094847
2004	20.11490485714874
2005	19.605436088942252
2006	19.3231963450217
2007	19.21503339927429
2008	19.103416481503697
2009	18.894494857422355
2010	18.720468885946133
2011	18.468825693723215
2012	18.289069095198343
2013	18.026434940158715
2014	17.88484766070467
2015	17.866613534890615
2016	17.990574816095787
2017	17.54610961404439
2018	17.338849708572766
2019	17.09763190950875