| Year | Value | | 2022 | 57.421041129068 | | 2021 | 51.445194879438 | | 2020 | 41.781768145829 | | 2019 | 46.150752065446 | | 2018 | 49.742094809243 | | 2017 | 46.599948192449 | | 2016 | 43.361592906094 | | 2015 | 45.568945990797 | | 2014 | 55.749361080545 | | 2013 | 58.25197258937 | | 2012 | 60.329170060905 | | 2011 | 60.099294381988 |
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