Year % 2007 2.29637920040576 2008 3.1090344283813 2009 4.33080924700152 2010 4.6936814254669 2011 6.37513416721368 2012 8.1867265178227 2013 9.21340777024835 2014 10.448048080803 2015 16.7400634913285 2016 16.5658132039701 2017 13.1873609272177 2018 9.42696352418473 2019 6.18151003441012 2020 4.8872570305011 2021 3.68197985762537