Occidental's environmental remediation liabilities fluctuate based on various factors, including acquisitions or divestitures, the identification of additional sites, and the selection of remedies. For the years ending December 31 2020 and 2019, Occidental recorded environmental remediation expenses of 28 million and 112 million, respectively. This is primarily due to changes in existing conditions from past operations, and Occidental estimates that approximately 40 of its remediation budgets will be spent over the next three to four years, with the remainder remaining over the next 10 or more.