Year	Percent
1990	2.713
1991	2.598
1992	2.487
1993	2.353
1994	2.383
1995	2.431
1996	2.527
1997	2.584
1998	2.616
1999	2.705
2000	2.786
2001	2.84
2002	2.865
2003	2.911
2004	2.984
2005	2.75
2006	2.533
2007	2.333
2008	1.77
2009	2.069
2010	2.107
2011	2.163
2012	2.223
2013	2.287
2014	2.345
2015	2.447
2016	2.533
2017	2.481
2018	2.428
2019	2.375
2020	2.322
2021	2.27
2022	2.217
2023	2.164
2024	2.111
2025	2.059
2026	2.006
2027	1.953
2028	1.901
2029	1.848
2030	1.795