How to Sum many values at specific date

[#1]

I have a many values and manydates. When the user selection a date, in the table must be have 3 columns:

Sum atmonth  selection , sum at month selection-1( previous ), sum at month selection -2 ( previous-previous ).

Who canhelp me =/

[Oleg_Troyansky]

I'd recommend adding a new field in your Calendar and to assign a numeric representation for the month number. For example:

MonthNumber = Year*12 + Month.

This way, MonthNumber-1 will always represent the previous month and MonthNumber - 2 will always represent the month before previous.

With this field, your 3 expressions would look like this:

sum({$<MonthNumber = {$(=only(MonthNumber))}>} Value)

sum({$<MonthNumber = {$(=only(MonthNumber)-1)}>} Value)

sum({$<MonthNumber = {$(=only(MonthNumber)-2)}>} Value)

regards,

Oleg Troyansky

[#3]

I wasn’t really clean in my question, this is the point:

Sum many values the months until the month selected. Example:

Sum at month  selected , sum until month selection -1( previous ), sum until month selection -2 ( previous-previous ).