Can you please explain furthur?

When we create a field number of records with a value of 1, we are creating a new column "number of records" in the data where every value is 1. Then if we apply the sum of the number of rows columns with respect to the filters, we will get the number of rows.

me too , I didn't understand it

I agree that it is not clear why "1" represents the Count of records. When I investigated the "Number of Records" Calculated Field further (Describe Field) The Default Aggregation is "Sum." That *then* made sense that this newly created Calculated Field aggregates (or sums). The value "1" itself is a multiplier applied to the Aggregate. If you were to input "2," you would receive 2x the number of records and so on.