First of all, thanks for this dashboard! In this visualization, we are subtracting the same value from itself which results in a 0 value. <img width="1470" alt="image" src="https://github.com/aaukhatov/grafana-dashboards/assets/13780335/00667bda-29e8-4d20-8232-9e9e792c367e"> I believe that this is a bug.