As Germany is preparing to register a millionth refugee I discovered that UNHCR maintains great website visualizing flow of refugees/migrant throughout Europe (http://data.unhcr.org/mediterranean/regional.php), along with graphs showing number of arrivals in each country. I combined data for all of the the countries along the west Balkan route, which enables us to track time delays as people are arriving from one country to another.
Seemingly distant event, such as shipping strike in Greece sends reverberations along the whole route, creating a short dip in arrivals and then spike as the bottleneck gets released. Also significant event was closing of border by Hungary, which immediately resulted in movement of refugees/migrants through Slovenia which has not been part of the route until that point. Movement can be much better traced in later months (e.g. notice how well traced is the last peak that start in Macedonia in early December and which ends in Austria just few days latter). I assume that this is because the methods of accepting and transporting refugees/migrants and general organization levels are much higher now that at the beginning of the fall.