Histograms of distances between the positions of the merging events to the closest sunspot (top), position of the splitting events to the closest sunspot (middle), and between the gravity centres of the merging and splitting clusters and the closest sunspot (bottom). The histograms are plotted for the active regions in their emerging and formation stage (left) and for the decaying active regions (right). It is important to take note of the logarithmic scales on the vertical axes.