Conditional days between dates (based on previous rows)

[kcmuppet]

Hello,

I'm new to Power Pivot Power BI and would appreciate some help trying to work out a Calculated column or Measure that is a conditional count of days like the example in the picture

I need a count of days...
... if the Name matches a Name already in the column and...
... since the last "Event type A" for that matched Name

I can't much past "=if ( [Name] = [@Name] , if ( [@Event] <> "Event type A", ....

Would greatly appreciate somebody pointing me in the right direction

 

[kcmuppet]

I'm thinking the calculation needs to be a MAX value, filtered? Something like: 'Find the max date date by filtering the Event and Name , where the name 'equals the Name on the current row.'

So to start with I'm trying to work out what the effective equivalent in DAX is of the "@" in an Excel table. Is it right that I can use the EARLIER function?

I'm not getting very far with this:


=calculate(MAX(tbl_Events[Event date]),FILTER(ALL(tbl_Events), tbl_Events[Name] = EARLIER(tbl_Events[Name]))


Any tips greatly appreciated.

(Now cross-posted here)