Summing the prior month

[#1]

The syntax here for summing the records for the previous month is not working.

Any suggestions on the correct syntax

=Sum ({$<[Period (FDPERD)]={"=(only([Period (FDPERD)]))-1"}>}[TR Outstanding (TROUTV)])

Thank you

[#2 · Accepted solution]

You could try:

sum( {$<Period= {"$(=Num(Period-1))"}>} [TR Outstanding (TROUTV)])

[#3]

I have 2 suggestions for you:

sum( {$<[Period (FDPERD)] = {$(=Only([Period (FDPERD)])-1)}>} [TR Outstanding (TROUTV)])

or

sum( {$<[Period (FDPERD)] = {$(#=Only([Period (FDPERD)])-1)}>} [TR Outstanding (TROUTV)])

Hope these work!

Best,

Maya