The system ranks does not rank ads by view volume, as that can be raised with paid placements, but a combination of organic views, paid views, watch time and audience retention. As a result, some lesser-viewed spots ranked higher when all metrics were taken into account.
One of the annual top spenders, John Lewis, took the top spot with 11.7m views. Supermarkets dominated the top ten, but tech companies also pushed their way into the mix.
Watch the ads below.