Scottish Transport Statistics No 34 2015 Edition
Road Transport Vehicles
1. The "Household Reference Person", or HRP, was introduced in the 2001 Census to replace the concept of the "head of the household". This allows a household to be further characterised using the properties of the HRP. The HRP is taken as the adult in the household with the highest economic activity – if the two people have the same economic activity then the oldest becomes the HRP.