The tephra produced by the eruption was used to extend the runways at the island's small airport, and also as landfill on which 200 new homes were built. By mid-1974, about half the pre-eruption population had returned to the island, and by March 1975, about 80% had returned. The recovery and reconstruction of Heimaey was paid for by all Icelanders via a hypothecated sales tax, as well as through international aid totalling US$ 2.1 million primarily from Denmark but with substantial contributions from the United States and several international organisations. With the harbour improved by the new lava breakwater, the fishing industry regained its former vigour and the island today remains the most important fishing centre in the nation, as over a third of Iceland's total fish catch is from this harbour.