Dynamic Matrix? Is this possible?

Been pounding my head off the desk today. Thought I had this figured out and now I'm just tinkering to the point where I'm at a loss...

I have visitors shopping and spending money. I want to track this in a matrix that both knows to assign each customer a spot in the matrix based on how many visits within this time period, but also how much they spent during this time period.

For example, Customer X might spend $800 in January and visit the store 6 times. This would fall into column 4-6 visits, row 0 - 1000 sales. However if I change the filter to February, we see this summation fall under a different column and row intersection on the matrix.

Is this possible? It sounds so simple and obvious but I'm just stuck.