Could you please upload mock-up data.
Sure, here is an example. For the first sheet, I would like to calculate daily average for the period BUT only starting on the first day of data because the second product did not start until the 14th of that month.
The second sheet is sum of sales per month by product. I want to create another sheet that has DAILY AVERAGE by month BUT again it only takes from the point where the product starts AND it only takes the last day of the most recent month. For example, in March, the data only goes to the 22nd so the average should only be over 22 days.
Lastly, I would like to create a full year that takes the daily average over each month.
Does this make sense? Spreadsheet attached.