The Department for Transport provide annual average daily flows (AADFs) at local authority level. They are calculated using a combination of manual and automatic traffic counts to give a series of AADFs (average vehicles per day) for each count point.
The daily flows are combined with road lengths to calculate the number of vehicle miles travelled each year. Authorities within NECA that have large rural areas, County Durham and Northumberland, have relatively low AADFs. Areas with low AADFs can still contain roads that suffer from congestion.
Source: Department for Transport, National Road Traffic Survey (Table TRA8907)
Data information: The Department for Transport provide supporting information, including definitions and methodologies, on their road traffic statistics here.