This chart displays your purchases for the past 12 months. The coloured bands show how much of each months purchases was contributed by each type of risk category. For example if you have a large portion of red in a particular month then this means you bought a large amount of supplies from 'Maximum Risk' or 'High Risk' companies. 

Having a large portion of red could be of concern if these suppliers supply critical goods or services that you cannot easily replace. If the goods or services are critical to your business then you should seek some form of guarantee of supply or have alternative suppliers in-place and ready to take over should one or more of your current suppliers fail. 

The chart will start all grey since you will not have monitored any companies for the past 12 months. As the months go by the chart will fill in the appropriate colours and values. Initially, it maybe worth monitoring your top suppliers so this chart starts being filled in. 

Note: If a company moves from one risk category to another, the historical information in this chart will change, therefore it is a true reflection of your past exposure to risk.