Who is born as a Variant Human is completely random and doesn't seem to be dependent on any outside factors.

We are also told that Variant Humans still make up a negligible percent of humanity in Blades and Barriers.

And that the most common type of VHs are Shifters.

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So let's do some quick math:

Let's assume that Variant Humans make up a 10th of 1% of the population(Making them the smallest minority in America).

So if you live in an averaged sized city with a population of: 200,000

The amount of Variant Humans you could find would be about: 200

And since Powereds outnumber Supers 2-to-1 then it would be:

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Around 133.33 Powereds

And around 66.67 Supers

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Most of them, if I remember correctly, will be(From most to least common):

* Standard Class[Thomas, Stella, and Camille]
* Non Threatening Combatant or "Knock"[Bubbles, L-Ray, and Dean Blaine]
* Demolition Class[Hexcellent, Raze, and Bloodfrye]
* Manhattan Class[(Hero)Vince]
* Armageddon Class[Globe and Black Hole]

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^ Needless to say these are averages and every place will fall either below or above those numbers.

Also: I think it's completely random whether or not a Variant Human will have irregularly colored features.