last 6 months total

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last 6 months total

Primary KeyDateqty last 6 months quantity sold
11-Oct40
11-Nov104
15-Dec2014
11-Jan334
11-Sep880

 

Hi All,

 

I have to calculate total quantity sold for last 6 months. For example in case of January 2018 , I have to calculate told quantity sold from July - Dec 2017. This total should be grouped by primary key. 

 

Thanks