Since 18 July 1994 the gross and net tonnages, dimensionless indices calculated from the total moulded volume of the ship and its cargo spaces by mathematical formulae, have been the only official measures of the ship's tonnage.
Nuo 1994 m. liepos 18 d. bendrasis ir neto tonažas, bedimensiai skaičiai, apskaičiuojami naudojant matematines formules, tapo vieninteliais oficialias laivų tonažo matais.