Monthly Average With Detail Data

[danielreber]

I have data at the day level but I would like to create an expression that calculates the monthly average for the last six months. I am currently using

=num(avg({< _M={13,12,11,10,9,8} >}total TransactionAMT*-1),'$#,##0')

with "_M" being the month number field and 8-13 being the last six months.  However, the calculation is averaging the data at the day level.  How do I calculate a monthly average for the last six months?

Thanks

Dan

[danielreber]

 I believe I figured it out using 

=num(avg({< _M={13,12,11,10,9,8} >} aggr(sum(TransactionAMT*-1),_M)),'$#,##0')

Is this correct?

[sunny_talwar]

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@danielreber wrote:

 I believe I figured it out using 

=num(avg({< _M={13,12,11,10,9,8} >} aggr(sum(TransactionAMT*-1),_M)),'$#,##0')

Is this correct?

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Looks correct to me