Year % of total labor force 2004 0.2699077185510274 2006 0.2540314795809496 2007 0.24804847859465654 2008 0.24247597063131043 2009 0.31560839916406425 2010 0.3085425994945646 2011 0.30060505242506913 2012 0.2931775597927918 2013 0.2848502501542046 2014 0.27685608063381306 2015 0.2695559825214226 2016 0.2632631166394166 2017 0.38460133187441226 2018 0.41181612784270116 2019 0.3688614537936479 2020 0.36298431181804325