Year number of cases 2008 1000 2009 7500 2010 1000 2011 10000 2012 16000 2013 13000 2014 1200 2015 5700 2016 3200 2017 31000 2018 11000 2019 25000 2020 51000 2021 49000 2022 17000 2023 4700