Year % (cumulative) 1981 9.41456031799316 2001 20.8212890625 2011 30.05592918396 2012 30.410530090332 2013 27.2711696624756 2014 27.6012001037598 2015 33.4365196228027 2016 33.9949607849121 2017 34.640869140625 2018 35.2952919006348 2019 35.9636116027832 2021 38.1519508361816