How do I display only negative results in a pivot (past two months)?

[#1]

I have a pivot and only want to display the results that were less than 0 for the prior two months (Green Highlighted in Image).  I do not want to display where one of the two months was >0 (Red Highlighted in Image).

[sunny_talwar]

Is this in a straight table or Pivot table? Straight table should be simply using

If(Expression1 < 0 or Expression2 < 0, Expression1)

If(Expression1 < 0 or Expression2 < 0, Expression2)

[#3]

Yes, this will work in straight table, my question was for Pivot where there is only one expression across many dates.

[johnw]

Possibly some use of above() or before(), but I hate using chart inter-record functions. I'd add an AsOf table to the data model to be able to reference the previous months. Then you'd end up with some sort of expression like this:

if( sum({<[MonthsBack]={1}>} Blah)<0
and sum({<[MonthsBack]={2}>} Blah)<0
,   sum({<[MonthsBack]={0}>} Blah))

The As-Of Table