Here’s some just-released census data. Scott Shaffer made this lovely chart breaking down population change in Minnesota’s 87 unique and individual counties.
Here you go:

Here’s what Shaffer says about it:
I made a chart showing the relation between the rate of population growth for each county and the population of each county in 2010. Big counties are gaining population, and many small counties are losing population.
This morning I saw another map about growth around the US, so these trends are part of a larger narrative.
EDITOR’S NOTE: Here’s a link to the Census Bureau’s county-level 2015 estimates for MN: http://factfinder.census.gov/bkmk/table/1.0/en/PEP/2015/PEPANNRES/0400000US27.05000
City-level 2015 estimates will be released in the coming months.