Simple stat panel with postgresql

I’m trying to display a timestamp to show the last updated date of some data. I’m using a stat panel where the field unit is ‘From Now’

I’m using postgresql, my query looks like this:
SELECT max(date) from county_metrics

I can see the value is coming back as an epoch timestamp from the query inspector, but the panel just shows “N/A” which is what the null value is mapped to. This seems like a simple thing to do so I’m not sure what i’m doing wrong here. Any assistance is appreciated!