5 million
The starting population, with the population size descriptor 'fledgling', and a population growth rate of 1 million per day.

7 million
The population size descriptor changes to 'tiny'.

10 million
The population growth rate increases to 2 million per day.

20 million
The population size descriptor changes to 'small'. The population growth rate increases to 3 million per day.

32 million
The population growth rate increases to 4 million per day.

40 million
The population growth rate increases to 5 million per day.

50 million
The population size descriptor changes to 'large'. The population growth rate increases to 6 million per day.

62 million
The population growth rate becomes randomly variable, ranging from 5 million per day to 7 million per day. The population growth rate does not change after this.

100 million
The population size descriptor changes to 'very large'.

200 million
The population size descriptor changes to 'huge'.

250 million
The nation can receive the issue to create a custom-named national capitol.

500 million
The nation name pretitle changes from multiple-choice to a custom text field. The player may submit issues from now on, at the issues page.

1 billion
The population size descriptor changes to 'massive'. The nation can receive the issue to create a custom-named national religion.

5 billion
The population size descriptor changes to 'colossal'.

10 billion
The population size descriptor changes to 'gargantuan'.