Year % 2008 7.67772566797717 2009 16.200000013472 2010 18.0818565043657 2011 14.1459892948403 2012 13.1966714743996 2013 11.9989351569178 2014 11.269173026949 2015 14.6736173400465 2016 17.2944005721658 2017 21.5912492157277 2018 18.1871529944043 2019 13.9419112610376 2020 14.7938784472408 2021 15.1166575274938 2022 14.7948102065664