Calculate a total between two dates

Hi, maurcoll 

You can try the following dax to achieve your need.

Before = 
VAR _minDate = CALCULATE(MIN('Table'[Offer Start Date]),ALLEXCEPT('Table','Table'[Customer]))
VAR _counts = CALCULATE(COUNTROWS('Table'),FILTER('Table','Table'[Order Date]<_minDate))
RETURN
_counts

Between = 
VAR _minDate = CALCULATE(MIN('Table'[Offer Start Date]),ALLEXCEPT('Table','Table'[Customer]))
VAR _maxDate = CALCULATE(MAX('Table'[Offer End Date]),ALLEXCEPT('Table','Table'[Customer]))
VAR _counts = CALCULATE(COUNTROWS('Table'),FILTER('Table','Table'[Order Date]>=_minDate && 'Table'[Order Date]<=_maxDate))
RETURN
_counts

After = 
VAR _minDate = CALCULATE(MIN('Table'[Offer Start Date]),ALLEXCEPT('Table','Table'[Customer]))
VAR _maxDate = CALCULATE(MAX('Table'[Offer End Date]),ALLEXCEPT('Table','Table'[Customer]))
VAR _today = TODAY()
VAR _counts = CALCULATE(COUNTROWS('Table'),FILTER('Table','Table'[Order Date]>_maxDate && 'Table'[Order Date]<=_today))
RETURN
_counts

Best Regards,
Yang
Community Support Team

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