Year	%
1999	18.4615384615385
2000	18.4615384615385
2001	18.4615384615385
2002	20
2003	20
2004	30.7692307692308
2005	30.7692307692308
2006	28.9855072463768
2007	28.9855072463768
2008	30
2009	30
2010	30
2011	31.3432835820896
2012	31.3432835820896
2013	31.3432835820896
2014	31.3432835820896
2015	30.4347826086957
2016	30.4347826086957
2017	31.8840579710145
2018	31.8840579710145
2019	31.8840579710145
2020	35.7142857142857
2021	35.7142857142857
2022	35.3846153846154
2023	36.6197183098592