From the NZ Herald:
Japan started the war with six million tonnes of shipping and of course built more as the war went on. US submarines sank 1314 of their ships of more than 1000 tons each, plus 700,000 tons of naval ships including eight aircraft carriers, a battleship and 11 cruisers.
They did 416 patrols and fired 14,500 torpedoes. Out of a total of 52 subs lost, 48 were lost operating from the Fremantle base. American submariners made up only 1.6 per cent of the US naval manpower but they had the highest loss rate of US Armed Forces with 22 per cent killed.
Read the whole thing.
Photo: USS Swordfish, sunk off Okinawa in January 1945