Monthly Ranking

[#1]

Hi all, nice to meet u and thanks for all help u give me on this question.

The company XXX assigns a score to each month of its sellers.
I want to extract the list of seller that have worsened their assessment, that is, those sellers, this month scored lower than previous month.
As can be seen in the attached file, the scores are not awarded every month so I should scroll through the months backwards until I find the previous value.
My question is to find a formula or any VB script to solve the problem.

thanks to all who help me.

best reguards

Gianluca