use of age() function postgres
You can do a AGEfrom you MIN date


CREATE tABLE &quot;table1&quot; (date_column timestamp)




INSERT INTO &quot;table1&quot; VALUES ( NOW())




SELECT AGE(MIN(date_column)) FROM &quot;table1&quot; 




| age              |
| :--------------- |
| -12:07:06.199423 |


db&lt;&gt;fiddle here