• Heidelberg Materials AG average operating margin for 2018 was 11.33%, a 7.96% increase from 2017.
• Heidelberg Materials AG average operating margin for 2017 was 12.31%, a 13.55% decline from 2016.
• Heidelberg Materials AG average operating margin for 2016 was 14.24%, a 28.4% decline from 2015.

Operating margin can be defined as operating margin measurement of what proportion of a company's revenue is left over after paying for variable costs of production such as wages, raw materials, etc.