List of cities whose population has fallen under a million

This is a list of cities which have experienced significant population decline, otherwise known as shrinking cities or rust belt phenomenon. There are varying reasons for this, please see shrinking cities. For the purposes of inclusion in the list, we use data since 1900, a (city limit) population which has fallen under a million residents, having previously been over a million, with the trend not being attributable to a temporary event rather a long term trend (former million people cities). This list does not include cities which have amalgamated and/or no longer exist. Following the city name is the year of its peak population. Included are cities worldwide. Generally wars and catastrophes are a one-time event and do not constitute long term trends as populations in large cities tends to bounce back after war has ended.
List with peak population and year (please click on each city for current population)
* Detroit, United States - 1950 Census 1,849,568
* Dnipro, Ukraine - 1989 Census 1,109,102
* Glasgow, United Kingdom - 1961 Census 1,055,000
* Kitakyushu, Japan - 1980 Census 1,065,078
* Naples, Italy - 1981 Census 1,212,387.
* Perm, Russia - 2002 Census 1,001,653. Million-people status was regained, with a 2014 population of 1,026,481.
* Turin, Italy - 1981 Census
* Nova Iguaçu, Brazil - was million-plus city in 1989, but then cities of Belford Roxo and Queimados were split out.
* A handful of Russian cities were in danger of falling under one million residents after post-Soviet flight and decay. Demographic trends in Russia, including urban cores, have been reversed in the 2000s due to government interventions.
* Birmingham, United Kingdom - has fallen below 1 million on three occasions and bounced back in the next census; 1939, 1981 and 2001.