Hi Everyone,   I am stuck in one problem where I am not able to program it. Sample data is given below :      ID A1x B1y   Output AA 87500000 1750000000   87500000 AA 0 628420515.9   31421025.8 AA 0 603509371   30175468.55 BB                           40,000                800,000               40,000 BB 0 720,000   36000 CC                        440,250            8,805,000             440,250 CC 0            7,885,000             394,250 CC 0            6,458,720             322,936 CC 0            2,571,356       128,567.80   Output Calculation :  For AA OBS         output 1               87500000 2               (87500000/1750000000)*628420515.9 = 31421025.8 3               (87500000 +31421025.8 /1750000000 + 628420515.9) * 603509371 = 30175468.55   For CC OBS        Output 1             440,250 2             (440,250 / 8,805,000)*7,885,000 = 394,250 3              (440,250 + 394,250/ 8,805,000 +7,885,000)*6,458,720 = 322,936 4              (440,250 + 394,250+322,936/ 8,805,000 +7,885,000+6,458,720) * 2,571,356 = 128,567.80   I have tried with using lag and cumulative but not able to go beyond obs =2 and also got issue in implementing in the subgroup. I had a thought of using array and loop but it was making program quite complicated and also not getting the desired output.   Please help. ... View more