And here, it is called 'fun' rather than 'bu' to avoid mixing up with bu which was used as the currency unit of a gold coin, ichibu-kin (a former Japanese gold coin of 1 bu).
また「分」を「ぶ」と発音せず「ふん」と呼んだのは金貨の通貨単位である一分金（ぶ）との混同を避けるためである。