Year	Percent
1991	2.50159
1992	2.46206
1993	2.41598
1994	2.36548
1995	2.3042
1996	2.25317
1997	2.21228
1998	2.16107
1999	2.10983
2000	2.04381
2001	2.34492
2002	2.34165
2003	2.45951
2004	2.25562
2005	2.09652
2006	2.03228
2007	1.81992
2008	1.78668
2009	1.46113
2010	1.3367
2011	1.16574
2012	1.04326
2013	1.26243
2014	1.29242
2015	1.46763
2016	1.16813
2017	0.99788
2018	0.99466
2019	1.00538