The Forecast rows tab shows all the forecast rows that have been registered/imported for each sales forecast. Here you register new forecast rows on existing sales forecasts.
Each forecast gets a row number an on each row you enter a part number, the quantity you expect to sell and that should be reserved, and the delivery period. If you enter several rows, the system will calculate the delivery period for each row based on the first row's period plus the number of work days between the periods that was entered as the interval in the sales forecast.
A sales forecast can e.g. contain several forecast rows for the same part. The result will be a forecasted planning horizon for that part. The part can then be reserved with the entered quantity and an even period interval in the planning horizon, during requirements planning in either the Run Netting or Requirement Calculation procedures.
A sales forecast can also consist of a separate forecast row for several different parts, for example if it is a product group or a sales forecast for a seller. The parts in that product group, or for that seller, will then be reserved with the given quantity for one period within the planning horizon, when you perform requirements planning for that forecast in the procedures mentioned before.
At the bottom of the tab you will see a total of how many row that exist, how man part numbers and also how many parts that the forecast in question contains.