 Bustamante, at the age of 78, became the country's first prime minister.Strong economic growth, averaging approximately 6% per annum, marked the first ten years of independence under conservative JLP governments; these were led by successive Prime Ministers Alexander Bustamante, Donald Sangster (who died of natural causes within two months of taking office) and Hugh Shearer.The growth was fuelled by high levels of private investment in bauxite/alumina, tourism, the manufacturing industry and, to a lesser extent, the agricultural sector.