Year	Percent
1991	6.506
1992	6.546
1993	5.985
1994	6.421
1995	6.655
1996	6.581
1997	6.881
1998	6.709
1999	6.756
2000	5.965
2001	5.74
2002	3.742
2003	3.725
2004	3.713
2005	3.719
2006	3.628
2007	3.497
2008	3.468
2009	3.641
2010	3.627
2011	3.91
2012	4.483
2013	4.759
2014	4.837
2015	4.811
2016	4.699
2017	4.604
2018	4.516
2019	4.43
2020	4.353
2021	4.276
2022	4.202