Power BI Calculated Column dependent on previous value of self

Hello,

I wonder if anyone could help with this calculation. I have a calculated table with the following fields among others: KeyId, Date, CumPnl.  Note that CumPnl is already a calculated column.

I would like to add a new calculated column Peak, where let's say for example that the equivalent excel formula for the current row i would be:  

Peak[i] := IF ( CumPnl[i] > Peak[i-1], CumPnl[i], Peak[i-1] )

The rows could be differenciated by date or key. 

I somehow cannot get the EARLIER() syntax right in conjuction with IF and the circular dependency.

Any ideas?

Many thanks,

Jose