Year % 2014 19.8982496745725 2015 20.465913739049 2016 19.5263074044408 2017 17.7493729526901 2018 15.9261493408989 2019 15.4438791390998 2020 15.3815442567175 2021 14.733190668004 2022 13.4592327554287