Sentence:  This trade was subject to a tariff of 7.5 per cent after February 1835 , but much was smuggled into Assiniboia with the result that the duty was reduced by 1841 to 4 <WSD>per</WSD> cent on the initiative of the London committee . 
Meaning of the word marked with <WSD> tags:  a proportion in relation to a whole (which is usually the amount per hundred)