It seems that we have one and the same problem without getting any sympathy and talk about counting regional pages (countries) related to the global page.
The global_brand_like_count metric leaves in a week or so, and I'm not sure if there is a good replacement if you do not have access to data (access to personal data) to a specific page. With this access, you can use the page_fans label.
I'm afraid you misunderstood the list of countries represented by the page_fans_country tag. Facebook’s description suggests that this metric is “Grouped Facebook location data, sorted by country, about people who like your page.” To give an example, for the Dove Switzerland regional page, you’ll be presented with a list of the best countries that liked the page, or rather, the number of users by country. In fact, there are only 9 now, but if there are people from 58 countries who like this regional page, Facebook has provided only 45 of the best. And this returns 45 countries, if there are so many.
To get your favorite life (page fans) for a regional page, one idea is to summarize all the numbers in the returned list. The only problem is that users from more than 45 countries who like this page will get the wrong amount less.
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