Year % (cumulative) 1971 7.9289698600769 2006 30.3977870941162 2007 31.6042976379395 2008 30.6981220245361 2009 31.4906005859375 2010 33.7010917663574 2011 33.0590400695801 2012 36.9503593444824 2013 37.8567390441895 2014 38.9803009033203 2015 39.7894134521484 2016 40.5749015808105 2017 44.0941696166992 2018 41.593090057373 2019 42.9992599487305 2020 47.2437782287598 2021 48.6701393127441