Charting help needed

Dear Experts, 

                    I have a data as below, 

So , in Column "G" we have 2 Rntis( 21,8,66 & 53714), and I need to plot the time difference for report of each rnti, which is calculated by subtracting the consecutive - SFNs, for that rnti.

Now , the problem here is that in below for example , for the rnti-53714, it's not correct, for example at row-244, my last report for rnti=53714 came at row 241, so the difference should be (821-789) * 10, while in my case it's doing the subtraction in consecutive SFNs, which basically messes up my analysis.

I tried to do something like below from column W to AF, but not sure how to achieve this properly( X axis should be my time, Y axis should be my average-ms and distribution should be based on the RNTI.

Attached is the worksheet..(anything in -ve and above 400 is Outliers and need to be removed) in ms column also.

Thanks in Advance!

Br,

Anupam