The five countries are: UK, France, Germany, Russia, and China. The data used for demographics is as up to date as I can find but as France and Germany don't collect ethnic data, I've had to use different metrics.

British adverts:

The ethnic make up in the adverts: White: 25/61 = 41% Non-white: 36/61 = 59% The actual make up of the UK: White: 81.7% Non-white: 18.3% Source:

French adverts:

This French advert isn't relevant to this thread, but I like how English they sound when saying "fish and chips". There's also a mixed race family, for some reason...

The ethnic make up in the adverts: White: 8/18 = 45% Non-white: 10/18 = 55% The actual make up of France: European origin: 85% Foreign origin: 15% Source (no ethnic data, estimate from 2004):

German adverts:

The ethnic make up in the adverts: White: 14/26 = 53% Non-white: 12/26 = 47% The actual make up of Germany: European background: 71.3% Foreign background: 28.7% Source (no ethnic data, only counts "backgrounds"):

Russian adverts:

The ethnic make up in the adverts: White: 18/18 = 100% Non-white: 0/18 = 0% The actual make up of Russia: White: 80.85% Non-white: 19.15% Source (2021 census):

Chinese adverts:

The ethnic make up in the adverts: Han Chinese: 18/18 = 100% Other: 0/18 = 0% The actual make up of China: Han Chinese: 91.1% Other: 8.9% Source (2020 census):

With this, we can see that the UK is the worst offender around this, over representing non-white ethnic groups the most. France are marginally better, with Germany the least-worst. Overall, the Western nations all over represent ethnic minorities in advertising.

In comparison, Russia and China present only ethnic homogeneity in advertising, only presenting their largest ethnic groups, and are both the closest representation to the actual demographics of their nations.