In my life, all but 2 of Wisconsin's largest cities have gained population

Sources:  1950 (Sporcle), 2016 (Wisconsin Blue Book 2017-18)

Since 2000, Madison's population has increased 21.3% -- an additional 44,497 residents.

Since 2000, Waukesha's population has increased 11.6% -- an additional 7,538 residents.