Kautilya's Arthashastra 3.11.2

3.11.2

tataḥ paraṃ kartuḥ kārayituś ca pūrvaḥ sāhasadaṇḍaḥ, śrotṛṛṇām ekaikaṃ pratyardhadaṇḍaḥ //

AN interest of a pana and a quarter per month per cent is just. Five panas per month per cent is commercial interest (vyávaháriki). Ten panas per month per cent prevails among forests. Twenty panas per month per cent prevails among sea-traders (sámudránám). Persons exceeding, or causing to exceed the above rate of interest shall be punished with the first amercement; and hearers of such transactions shall each pay half of the above fine.