Year	%
2000	2.7659287828587
2001	2.84212938129898
2002	2.96102611312729
2003	2.95580725329287
2004	3.03904829789605
2005	2.98166842922672
2006	2.94826289424382
2007	2.70208812605246
2008	2.79217428582137
2009	3.23143443739258
2010	3.31628599838433
2011	3.40970283561995
2012	3.45924683313978
2013	3.37220960362973
2014	3.39021991181451
2015	3.28145857487618
2016	3.27602405419969
2017	3.16547320433127
2018	2.83973767988328
2019	2.73802413097154
2020	2.74533752930224