This is a sample project from DataMarket's visualization gallery.
The video shows the urbanization of Iceland during the last century or so. Each bubble represents a single municipality and the size of the bubble (its area to be exact) represents the population. The animation also happens to show any activity in municipalities’ splitting and merging, especially in recent years.
Representing the population of – what may be a relatively large – municipality as a single point is not entirely accurate, but will nevertheless give a decent picture of the development in the country as a whole. A more fine grained (and fully accurate) population projection would involve plotting single farms and addresses, will involve a lot more data and preparation work and will await another day.
The population data we’re using comes from Iceland Statistics. Location data comes mainly from Geonames, with a few additions and corrections of our own. Data about mergers and splits of municipalities comes from Iceland Statistics and Wikipedia. The base for the background map comes from Samsýn and Gísli Sverrisson helped with the map projection algorithms.
Further details on this project can be found on the DataMarket blog