Etymology and distribution of 入月.

The Japanese surnames etymology dictionary.
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Popuration of 入月.

Etymology of 入月

Distribution of 入月
Ranking
1 Shizuoka-ken(About 200)
2 Yamanashi-ken(About 90)
3 Toukyou-to(About 90)
4 Kanagawa-ken(About 70)
4 Iwate-ken(About 70)
6 Aichi-ken(About 20)
7 Tochigi-ken(About 20)
8 Saitama-ken(About 10)
9 Gunma-ken(Very rare)
9 Shimane-ken(Very rare)
9 Chiba-ken(Very rare)