Facebook's advertising platform allows advertisers to target the users of Facebook, Messenger, and Instagram based on a large number of user characteristics, including age, gender, education, relationship status, interest, political affinities, etc. Once all the attributes of interest are specified, Facebook provides an estimate of the daily and the monthly number of users who satisfy the criteria. The estimates are free of charge, and if the process is repeated enough times without purchasing the ad, it is possible to build a substantial data set. Facebook provides programmatic access to these estimates through its API. We collected information about the users classified as Serbian Expats – people who lived in Serbia but now reside in another country. The estimates of the numbers of Facebook expats were calibrated to estimate the total number of Serbian migrants in a country. Explore the full results or read about the methodology. The figures below present the current number of Serbian migrants in each country around the world and the trends since October 2020. The goal of this project is to re-estimate these numbers every several months and investigate the migration patterns, especially in the post-Covid era.