Year % 2006 23.726 2007 20.27 2008 33.346 2009 27.67 2010 30.164 2011 22.598 2012 23.028 2013 21.416 2014 24.157 2015 24.184 2016 18.782 2017 18.83 2018 26.118 2019 25.43 2020 24.89 2021 20.175 2022 24.09 2023 27.898