I want to subtract cell D3 from cell D2 but only if cells B3 & B2 have the same value. if cells B3 & B2 are not equal, I want the formula to detect the next two cells that contain the same values and subsequently deduct their respective values in column D. In this case the values in cells B5 & B4 are not equal, hence the formula should check cells B5 & B6 and if they contain the same value deduct the values in cell D6 & D5 (D6 - D5).
Thank you in advance.
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Thank you in advance.
| Column B | Month | Column D | Value |
| 900 | 01-Jul-15 | 8140 | 8140 |
| 900 | 01-Aug-15 | 14999 | 6859 |
| 900 | 01-Sep-15 | 20978 | |
| 901 | 01-Jul-15 | 9000 | |
| 901 | 01-Aug-15 | 14633 | |
| 901 | 01-Sep-15 | 19715 | |
| 902 | 01-Jul-15 | 8338 | |
| 902 | 01-Aug-15 | 12799 | |
| 902 | 01-Sep-15 | 17059 | |
| 903 | 01-Jul-15 | 8913 | |
| 903 | 01-Aug-15 | 13960 | |
| 903 | 01-Sep-15 | 18475 |
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