Create New Column From Min Date in Other Columns

Hello,

I need to create a new column that has the minium date of 3 columns for each row in my table. I am trying to do this in power query. I tried each List.Min([column1], [column2], [column3]) but that errored. Message

Expression.Error: We cannot convert the value null to type List.
Details:
Value=
Type=Type 

Some of the columns do have null values for all so I think I need to add argument before hand if all 3 columns are null then return null otherwise but not sure how to right that.

Thanks for any help.