A special case occurred in the year 720 when 11 kanko were made ryonin and 10 kunuhi were made kanko but in 'Hamana-gun Yosocho' of 740, the status of ryomin is referred to as kanko, leading to the belief that the status of kanko among the senmin class ceased to exist in the first part of the 8th century.
720年(養老4)に、臨時に官戸11人が良民に官奴婢10人が官戸にされたことがあるが、740年(天平12)の「浜名郡輸租帳」では良民の戸を官戸と称しており、賤民としての官戸は8世紀前半のうちに実態がなくなったと思われる。