Work permit extension

As my work permit will expire at the end of August, I posted my application for its extension today. The Migrationsverket (Sweden's immigration office) apparently wants to pick a fight with foreign researchers. In the application form for foreign visiting researchers, one field to fill in is entitled:

Permanent address in Sweden

I moved in April of 2009, June of 2010, and September of 2010. I'm moving next month, at the end of July, and next May. What is my permanent address in Sweden?

(If you don't understand why I --- and most foreigners in Sweden --- have moved, and will move, so often in Sweden, see this post.)