Year Sterling (millions) 2011-12-31 17189 2012-12-31 15133 2013-12-31 13869 2014-12-31 15911 2015-12-31 14971 2016-12-31 15248 2017-12-31 15878 2018-12-31 15880 2019-12-31 15457 2020-12-31 20330 2021-12-31 18443 2022-12-31 18445 2023-12-31 16948