Year	Percent
2000	18.1421
2001	18.13217
2002	18.12404
2003	18.11591
2004	18.10733
2005	18.2143
2006	18.32151
2007	18.42894
2008	18.5366
2009	18.58365
2010	18.62994
2011	18.67508
2012	18.71988
2013	18.76937
2014	18.82328
2015	18.88129
2016	18.94311
2017	19.00846
2018	19.0774
2019	19.14929
2020	19.22383
2021	19.26172
2022	19.30473