I was curious about this because some nations churn them out every month, and others, regardless of how huge, hardly get any. Even with relatively similar domestic policy settings, I find a country like China hardly gets any colonists as compared to nations like Portugal or Spain or England or France. At first I thought it was just population size of your empire, but this clearly cannot be the case for China, or else it would get a ton of colonists.
What all increases the rate at which you get colonists?
What all increases the rate at which you get colonists?