Tonnage and poundage to be one of the complaints of his Long Parliament. The refusal of and subsequent disputes about tonnage and poundage rights is seen as one of the many events bearing responsibility for the English Civil War. Tonnage and poundage Tonnage and Poundage were certain duties and taxes first levied in Edward II's reign on every tun (cask) of imported wine, which came mostly from Spain and Portugal, and on every pound weight of merchandise exported or imported. Traditionally tonnage and poundage was granted by Parliament to the king for life until the reign of Charles I. Tonnage and poundage were
Net tonnage NT formula. It is based on three additional variables: First, a multiplier K, based on the ship's gross tonnage is found, formula_5 Then the net tonnage is calculated: formula_6 Where the factor formula_3 shall not be taken as greater than unity, the term formula_4 will not be less than 0.25 GT, and the final value of NT shall not be taken as less than 0.30 GT. The difference between the cases of 12 of fewer passengers and 13 or more passengers is due to a restriction given in the net tonnage definition that states "...when N + N is less