Year per 1,000 population at risk 2000 18.790091208644245 2001 18.739546542208224 2002 17.403020149588023 2003 17.97293948588361 2004 18.801906694760785 2005 19.877461704860092 2006 16.066823450620205 2007 15.423904825262456 2008 15.738805207523539 2009 15.958512351654779 2010 15.681155289920023 2011 13.806270427767195 2012 11.069720171728463 2013 8.636522195390171 2014 8.458515388204924 2015 8.900051541155216 2016 9.325067274641668 2017 7.163553703885964 2018 5.208439909016453 2019 4.21248829204191 2020 3.5848684516521865 2021 3.4195258614496633 2022 3.9331126564533143