Millward Brown is no stranger to the task having now held the account for 21 years.

In discussing the changing nature of chart tracking Bob Barnes, head of the Millward Brown Charts’ Unit, said: “The music and video markets are incredibly dynamic and both are experiencing a significant period of change with the introduction of subscription and streaming services as new ways to digitally consume music and video.”

Millward Brown will collect data from high street and online retailers in the UK and Northern Ireland. Subcription and streaming services, like Spotify, have recently been added to the audit.

For the first time additional reporting will be available on the OCC online system. OCC subscribers will be able to to dynamically interrogate sales data for any item of audio or video product at any time since 1994.

The Official Charts Company compiles the UK’s audio and video charts – including the Top 40 singles, albums and video charts.