Activity before and after a date

[domtrump]

I have customer records in a table with all sales activity. For each customer, there is a single trigger date for a particular event (when they became a loyalty member). Every customer's trigger date will be different. I'm looking for a pattern that will summarize the patrons sales data for the six months prior to the trigger date (and then I'll use the same pattern to get the six months after for comparison). How do I go about this?

[FreemanZ]

hi @domtrump 

try like:

Diff = 

VAR _triggerdate =

VAR _currentdate = MAX(TableName[Date])

VAR _salespre =

CALCULATE(

    SUM(TableName[Sales]),

    TableName[Date] >= EDATE(_currentdate, -6),

    TableName[Date] <= _currentdate

)

VAR _salesafter =

CALCULATE(

    SUM(TableName[Sales]),

    TableName[Date] <= EDATE(_currentdate, 6),

    TableName[Date] >= _currentdate

)

RETURN

_salesafter - _salespre