Last month cumulative measure not working

[crobson29]

I am trying to create a line chart that shows cumulative sales for both the month selected by a slicer and the previous month.  I have built a measure for cumulative sales for the current month that works correctly, the measure is:

Current Month = TOTALMTD(SUM(VW_FACT_SALES_DOCUMENT_ITEM_DATA_USA[Weight (Gallons)]), 'M_CALENDAR_BILLING'[Date])

The prior month is what is giving me trouble.  I have this measure built:

Prior Month = TOTALMTD(SUM(VW_FACT_SALES_DOCUMENT_ITEM_DATA_USA[Weight (Gallons)]), PARALLELPERIOD('M_CALENDAR_BILLING'[Date], -1, MONTH))

But this only gives me the total for the whole month.  This is what the chart currently looks like:

How can I get the prior month measure to give me a cumulative sum for each day, like the current month measure?

[crobson29]

This is exactly what I was going for, Thank you!

[v-jingzhan-msft · Accepted solution]

Hi @crobson29 

You can use this measure for previous month

Previous Month = CALCULATE(SUM(VW_FACT_SALES_DOCUMENT_ITEM_DATA_USA[Weight (Gallons)]),DATEADD(DATESMTD('M_CALENDAR_BILLING'[Date]),-1,MONTH))

Best Regards,
Jing
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