In areas where there are multiple complex constraints affecting a number of customers over a long time period, an Active Network Management (ANM) system will be implemented. Distributed control systems continually monitor limits on the network and then allocate the maximum amount of capacity to customers in that area based on the date their application was submitted. This dataset contains the number of minutes per ANM zone that curtailment occurred. Further details can be found [here](https://www.westernpower.co.uk/our-network/active-network-management-anm).