Year	Percent
1991	4.12
1992	4.865
1993	4.447
1994	3.939
1995	3.714
1996	3.516
1997	3.35
1998	3.074
1999	2.98
2000	2.839
2001	2.822
2002	2.777
2003	2.677
2004	2.638
2005	2.276
2006	2.226
2007	2.145
2008	1.833
2009	1.879
2010	1.764
2011	1.873
2012	1.834
2013	1.838
2014	1.645
2015	1.636
2016	1.622
2017	1.618
2018	1.57
2019	1.532
2020	1.497
2021	1.469
2022	1.445