Matoran Population Percentages?

So, approximately how common is each type of Matoran? Presumably Matoran of the 6 main elements were the most common, but how common were Av-Matoran? Or Matoran of Iron, Sonics, Gravity, the Green, Psionics, etc.?

Well, Av-Matoran lived in the caves above Karda Nui, save for a few like Takua, so I’d say that they’re relatively rare, and I heard that Matoran of Gravity are too.