Year	Percent
1992	28.00397
1993	27.80536
1994	27.25919
1995	26.71301
1996	26.06753
1997	24.57795
1998	24.32969
1999	24.82622
2000	25.71996
2001	25.32274
2002	25.07448
2003	25.32274
2004	24.429
2005	25.27309
2006	24.37934
2007	24.72691
2008	30.70356
2009	31.02979
2010	30.96663
2011	30.80562
2012	30.36827
2013	30.29841
2014	30.5283
2015	30.60628
2016	30.65634
2017	30.54111
2018	30.39272
2019	30.40663
2020	30.31773
2021	30.34107