Established on July 4, 1930. Badge was worn on the left chest as an enumerator ID badge. Surveyors were allowed to keep the badge after the end of survey.
Taiwan version of the badge https://asiamedals.info/threads/government-general-of-taiwan-census-takers-badges.24400/#post-364646
Karafuto...
1930 japan national census taker’s badge
1930年國勢調査徽章
badge made by suzuki workshop
imperial medal works
japanese national census badge
japanese national census medal
japanese national census taker’s badge
日本帝國徽章商會
昭和五年國勢調査徽章