One benefit - One advantage

…When rice or wheat was borrowed, the term was one year, compound interest was not permitted, and interest could not exceed 5% per year. There was also a rule that the amount of interest could not exceed the amount of the principal, and during the Yuan, Ming, and Qing dynasties, this was called ippon ichiri. Thus, the legal interest rates were by no means low, but the interest rates actually charged by usurers were even higher, ranging from 6% to 10% per month (120% per year). …

*Some of the terminology that refers to "Ippon Ichiri" is listed below.

Source | Heibonsha World Encyclopedia 2nd Edition | Information

…米麦を借りた場合には，期間は1年，複利は許さず，利息は年5分を超えてはならないとされた。また利息の額は元本の額を超えてはならないとする原則があり，元･明･清時代には，これを一本一利と称した。このように，法定利率もけっして低くはなかったが，現実に行われた高利貸の利率はさらに高く，月利6分以上から1割(年12割)に達するものもあった。…

※「一本一利」について言及している用語解説の一部を掲載しています。

出典｜株式会社平凡社世界大百科事典 第２版について | 情報