I'm stuck trying to solve the below excel problem.

I have a list of customer orders that I'm trying to compare with each other to get a percentage total. The percentage should identify the similarities between each order set based on the item type. So for example, the total number of orders under Matt would be compared with the total number of orders under Jennifer and Walter. There should be two seperate percentage totals for each customer. So in the example with Matt the percentage total would identify how similar Matts order is to Jennifer's order and there would be another percentage total that would identify how similar Matts order is to Walter's order.

I'm not sure how to tackle this problem and have been pulling my hair out in the research process to find a solution. I have tried approaching it from a one-to-many/many-to-many relationship but am not sure how it would work with a single list.

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