We have recently identified more data sources providing offline variables for the ownership of mobile phones expanding the number of countries this data is available for.
During recent review of our estimates, we found that daily values gathered from Facebook have been unstable. As a result, there have been day-to-day fluctuations for some countries in the online model estimates. We have switched the category of Facebook data we are using to Monthly Active Users (MAUs) as these are more stable than Daily Active Users (DAUs). The data for all previous reports have been revised to reflect this change.