Hi, I need some advice. Let's say I have a table with the expected sales "Table 1 - prediction", and on day 2024.01.01, I expected to sell 10000 items, and on 2024.01.02, 6000 items. However, the customer started buying two days earlier and finished 2 days later and created a distribution -2 days, -1 day, day 0, day +1, and day +2.
I need to create a new table, "Table 2 - real sale," with all days of the REAL sale (here between 2023-12-30 and 2024-01-04) and add my PREDICTED sale item. The color shows what I need to add up for each day of the actual sale. For example, on real sale day 2024-01-02, I need to add 1500 items from 10000 predicted of 01.01 (1500 customers bought 1 day after the predicted day) and 3000 from 6000 from predicted day 2024-01-02 as only 3000 purchased from predicted 6000 on this day 0. In short, the result table "Table 2 - real sale" should be a sum of the diagonal of predicted table "Table 1 - prediction".
My problem is that I don't know how to in the result table "Table 2 - real sale" for each day, make a sum of the function "Day SaleExpected" with appropriate column with day shift -2 days, -1 day, 0 days, +1 day, +2 days ect.
thanks for any advice.
