Occidental's environmental remediation liabilities vary depending on factors such as acquisitions or divestitures, the identification of additional sites, and the selection of remedies and implementation. 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 it is estimated that approximately 40 of the remediation budget for the next three to four years will result in the remainder of the remaining years.