The cross weight in volume expresses the weight in volume of two different universes A and B. It is broken down as follows:
Volume weight of universe A in pharmacies that only sell universe A
Volume weight of universe B in pharmacies that only sell universe B
Volume weight of universe A+B in pharmacies that sell universes A and B
This indicator measures the volume generated by pharmacies that are in different universes. It is expressed as a percentage.
Consider universes A and B in the following configuration:
In this case, we obtain :
pharmacies that sell only universe A have a volume of 1,000 boxes in universe A
the pharmacies that sell only universe B, have a volume on universe B of 1,500 boxes
pharmacies that sell only universes A and B, have a volume on universes A and B of 500 boxes
Thus, the weight of universe A in volume is 1,000 boxes / 3,000 boxes, or 33.3%.
The weight of universe B in volume is 1,500 boxes / 3,000 boxes, or 50%.
The weight of universes A and B crossed in volume is 500 boxes / 3 000 boxes, that is to say 16.7 %.