I've been struggling about creating the right formula field for the following function:

I want to create a field which gives the current date when a picklist field is given a specific value 'X'

The closest I get is:

Datepart(If(Contains(${Accounts.Klant-Fase (Woco)},'02. Overleg'))

But it keeps telling me I'm missing braces... 

And, will the date stick in the field when the picklist is altered to another value? Preferably it'll stay this date from the moment the value has been '02. Overleg' ...  

Anyone with a solution? 

Thnx!

Jim.