Hi,
First create col1 variable with condition =Max([Column_Name]) ForAll ([Column_Name])
Then create one more variable with condition ==If([col1]=[Column_Name]) Then [col1] Else 0
This will give you the max result. 180.
Same way you can create other variable for min. replace the max with min.
And how it will work try from your side.
Regards,
Amit