• Westlake average gross margin for 2023 was 20.33%, a 31.27% decline from 2022.
• Westlake average gross margin for 2022 was 29.58%, a 26.52% decline from 2021.
• Westlake average gross margin for 2021 was 23.38%, a 66.76% increase from 2020.

Gross margin can be defined as a company's total sales revenue minus its cost of goods sold, divided by the total sales revenue, expressed as a percentage.