Yes.
Define Time State rollup on inventory balance measure's properties Rollup tab to be Last period. Also uncheck on all of the Time dimension's levels Generate all categories in the period.
Then user sees inventory balance of the last period of the time dimension while sales in for the whole period, even though you bring in inventory balance for each month.
For example filtered by a year, user sees sales of the year, and inventory balance of year's last month or(/same as) last day.
Notice, if you have day level, all of the inventory balance values in data source must have as date the last date of the month. So for December, you have to have the date 12-31, 12-30.
Couple of "unless.." there, but it the big picture.
Cheers
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