Tonnage and poundage 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 swept away by the Customs Consolidation Act of 1787. Charles I's first Parliament, known as the Useless Parliament, broke with tradition and granted the king tonnage and poundage for a year rather than life out of
Net tonnage Sea. Otherwise, if a ship has been assigned a load line by its national government, the draft for that summer load line is used. If the ship has no load line, instead, a maximum draft assigned by its national government, that value is used, if it has been assigned a maximum. Finally, for a ship to which none of the above applies, the value of "d" is taken as 75 per cent of the moulded depth amidships. The Net tonnage calculation is defined in Regulation 4 of Annex 1 of "The International Convention on Tonnage Measurement of Ships, 1969". It