There have been plenty of maps showing the outcome of the Danish 2015 election, though I don't know of any (so far) that look at percentage changes.
I thought it would be interesting to take the percentage of votes each party earned in 2011 and see how those percentages changed in 2015.
How to use this
Clicking on a political party name will change the colors of the map (meanings defifned below).
Clicking on the party name again makes the menu visible.
Hovering over a district will show the district's name, and numeric percentage value.
How to read this
When a party is selected, the darker the color, the higher the change in the number of votes (expressed as percentage points) for that party in 2015 relative to the rest of the country. Let's take Radikale Venstre in Frederikshavn as an example.
In 2011, they received 1970 out of 41748 votes in Frederikshavn, giving them 4.7% of the vote. In 2015, they received 801 out of 40815 votes in that same district, giving them 2% of the votes. The change, as I'm calculating it, is -2.7%.
If we look at the average across the voting districts, however, (not normalizing for population) we see an average of -4.9% for Radikale.
So, though support for Radikale dropped across the whole country, we see that it dropped less in Frederikshavn than it did in the rest of the country. How much less? That's what the intensity of the color shows
Notes on methodology
Note that the change I'm calculating is different from percentage change (which could be written -59% in this case), and also different from net gains or losses nation-wide.
Also, as noted above, I'm not normalizing for population shifts or changes.
This means the types of conclusions that can be reached from this graphic are deliberately limited to discover possible trends in local initiatives.
For instance, we can say the people of Aarhus were much more amenable to voting for someone without a party in 2015 than they were in 2011, possibly indicating a positive trend for those wishing to run unaffiliated next election.
Similarly, we can say that Viberg Øst showed the greatest positive change towards Konservative, also possibly indicating a shifting locality of interest.