Why is my common metric cannot be displayed as Y-axis?

I created a metric, which is a sum and subtraction of a number of fields. The summation result in the preview seems right, when I created it.

When I apply it to a question, the metric shows in the table format. But all chart is greyed out. The metric values all in numeric. When I try to create line chart, the X-axis can be selected, but the Y-axis is disabled. Basically my metrics can only be shown in table format.

Is there anything I’m not aware of or maybe I skipped something when I created the metrics.



This is a high priority issue that we have been tracking in GitHub here: https://github.com/metabase/metabase/issues/3952

Thanks for your patience.