Darkspilver: Excluding the anomalies of very low publisher numbers and high ratio countries... It seems interesting there's really only three significant countries reporting similiar increases to Britain back in the 1980's, namely
Angola 1:210, 111,123 publishers, 8% increase
Philippines 1:499, 199,551 publishers, 5% increase
Russia 1:832, 172,977 publishers, 5% increase
I think the most likely reason for the supposed increase in Russia is the annexation of Crimea. If you look at the corresponding drop in Ukraine and do a back-of-envelope calc using Crimea's population, it seems to explain both the drop in Ukraine and the increase in Russia.
Angola's numbers are strange, especially when compared to some neighboring countries (the 2 Congos, Malawi). Also note that the increase in Angola is way above the number of baptisms.
In relation to Philippines, Watchtower seems to have more success in poorer Catholic countries, and perhaps this is an example of that. The ratio of publisher to population suggests there will be a lot more increase before there is a plateau.