Column passing "null()" returns "0"

unknown

I have date columns that are in YYYY-MM-DD that I use a formula tool using right() & left() to rearrange into a string MM-DD-YYYY. I change it to a string so I could keep the format when I pass it into a viz tool. I have null values for some of the dates so when I rearrange I get left with a record of "--" in the column. I use a second formula, as shown below, to check if the column has "--" and if so return the value to null. However, it is currently returning a "0". I am unsure why this is happening or how I could make sure that if the column is null leave it as is, but still updating the format if there is a date.

  

              

alee95

Hello, to my knowledge by setting your then clause to [Service Award Date] = Null(), it is evaluating it as a boolean expression and returning 0. Try just null().