Pivot Chart with Running Total

[krishna83]

Here is my Pivot table data.

Sum of total	Sales
Month	Actual	Target
Jul-15	1,041,824.00	1,043,486.13
Aug-15	1,289,003.30	2,000,141.25
Sep-15	1,289,003.30	3,013,169.74
Oct-15	1,289,003.30	3,945,066.89
Nov-15	1,289,003.30	4,914,635.34
Dec-15	1,289,003.30	5,655,860.49
Jan-16	1,289,003.30	6,391,296.91
Feb-16	1,289,003.30	7,259,339.87
Mar-16	1,289,003.30	8,180,282.95
Apr-16	1,289,003.30	9,042,537.17
May-16	1,289,003.30	10,002,576.48
Jun-16	1,289,003.30	10,915,148.16

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As you can see the Actual and Target (Sales) are cumulative totals. I got that using the show values as "running total in". My issue is data is linked to a pivot chart (line chart). My X axis is the month and Y axis is the Sales (two series - Actual and Target).
The chart depicts a linear increase for the Target which is right. For the Actuals, I want the chart to depict only Jul-15 and Aug-15 information.
In other words, I need pivot table not to calculate the cumulative sum for the months when the Actual value is 0. So I want my Pivot table to look like this.

Sum of total	Sales
Month	Actual	Target
Jul-15	1,041,824.00	1,043,486.13
Aug-15	1,289,003.30	2,000,141.25
Sep-15		3,013,169.74
Oct-15		3,945,066.89
Nov-15		4,914,635.34
Dec-15		5,655,860.49
Jan-16		6,391,296.91
Feb-16		7,259,339.87
Mar-16		8,180,282.95
Apr-16		9,042,537.17
May-16		10,002,576.48
Jun-16		10,915,148.16

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And every month when the values in the Actual column are updated, the cumulative sum needs to be done and it should also reflect in the Pivot chart.

Any help is highly appreciated.

Thanks,
Krishna