I've been wondering for a long time. Almost every time I see pictures of Japanese schoolgirls, they're wearing western-style school uniforms. Sailor uniforms seem to be worn by less than 10%, and it may be much lower than that.
So how rare are sailor uniforms nowadays? Do they basically only exist in anime, AV and a very small number of old-fashioned schools? Or is there still a decent number or schools that make the girls wear them?
I've also noticed that they seem to be more common as summer uniforms than winter ones. Any truth in that? Or am I just looking for patterns?

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