Year U.S. Dollars 2015-01-01 32111400000 2016-01-01 48237300000 2017-01-01 49278500000 2018-01-01 45001200000 2019-01-01 44790400000 2020-01-01 43407300000 2021-01-01 37542800000 2022-01-01 30011000000 2023-01-01 22649200000