Year % 2013 4.4176971883925 2014 3.90743164221445 2015 3.45940579970678 2016 3.42015574375788 2017 3.49731030066808 2018 3.47760649522146 2019 3.53355862696966 2020 3.30802353223165 2021 3.1007500688235 2022 2.95817645390829