Store Commander includes an option to calculate your products' margins automatically.
The margin is calculated with the wholesale price and the price excluding tax. The calculation is automatic and you therefore do not need to get your calculator out :-)
You will find more details on the calculation in Store Commander's interface > Tools > Settings > Interface > margin operation definition.
This is also where you set the calculation, and even apply a color to specific margin value.
You can choose a color for range of value.
For example, if the value is below 10, the cell will be red.
The formula to use will be 10:#BA2329
You can add as many formulas as you like using the format: 'value:#color code', as seen on the above screenshot.
Here are some color codes:
You can find all color codes on many websites, one of them being http://html-color-codes.info/color-names/