Number of countries with a given minimum urban population threshold, 2018

The number of countries which have adopted a given minimum population threshold (number of inhabitants) for classification of an 'urban area'. For example, 23
countries set a threshold of 2000 inhabitants or more in order to be classified as an urban area. There is no consistent definition of what constitutes an 'urban area'.
This is highly variable across countries. For many countries, there is no defined threshold based on inhabitants; other metrics such as population density,
infrastructure, or even pre-defined cities may be used.