(5)[ On the amount of a bill remaining unpaid after its presentation under sub-section (1) of section 149, simple interest shall be payable at such rate, not exceeding 10 per cent per annum, as may be determined by [the Board of Councilors] [[Substituted by the West Bengal Act 45 of 1994, w.e.f. 10.10.1994 old section read as :
