How to create a report that populate Cumulative Sum of Resolved cases per month
I am looking for an option to add a column in report definition which does a cumulative sum / running total.
For example, I have a following report,
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| Month | Resolved Cases |
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| 01 | 200 |
| 02 | 150 |
| 03 | 100 |
| 04 | 250 |
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Now, I am looking for option to add a cumulative sum of resolved cases,
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| Month | Resolved Cases | Cumulative |
-----------------------------------------------------
| 01 | 200 | 200 |
| 02 | 150 | 350 |
| 03 | 100 | 450 |
| 04 | 250 | 700 |
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Please advice on how to achieve cumulative sum.