If Operating Profit Margin increases over time:
An increasing Operating Profit Margin indicates the company has been more efficient in its day-to-day operations.
If Operating Profit Margin decreases over time:
A decreasing Operating Profit Margin indicates the company has been less efficient in its day-to-day operations.
If Operating Profit Margin stays the same over time:
An unchanged Operating Profit Margin indicates the the companys''s efficiency in its day-to-day operations has remained the same.