Create dimension based on values of another dimension
I work for an insurance company. A KPI for us is Premium Revenue by Agent. I have dimensions for Agent and for Premium. I want to be able to assign a score of 1 to 5 to each agent based on their premium volume. For example, if ABC Co. has greater than $5M then they deserve a score of 5. If less than $5m but greater than $2.5M, they deserve a score of 4. How do I create the "AgentPremiumScore" dimension and assign the value based on their volume and our scoring criteria?