Year Percent 2010-01-01 16.7488 2011-01-01 16.3476 2012-01-01 16.1996 2013-01-01 15.9347 2014-01-01 15.7942 2015-01-01 15.7227 2016-01-01 15.4730 2017-01-01 15.2629 2018-01-01 15.1228 2019-01-01 14.9427 2020-01-01 14.6750 2021-01-01 14.3923 2022-01-01 14.0911 2023-01-01 13.7833