Sorry, I remembered it backwards. IT's the rural areas which have the fertility rate around 2.3 (which I also remembered as little high, but only by a few %):

Sorry, I remembered it backwards. IT's the rural areas which have the fertility rate around 2.3 (which I also remembered as little high, but only by a few %): https://www.nippon.com/en/japan-data/h01975/ https://www.nippon.com/en/japan-data/h01975/