HONG KONG'S job market remained buoyant during the third quarter with effective full employment being maintained. According to statistics, the unemployment rate between July and September was 2.3 per cent and the underemployment rate 1.1 per cent. Provisional figures for the period from August to last month show there was little change with unemployment and underemployment being 2.2 per cent and 1.3 per cent respectively. The definition of full employment varies between countries. In Japan, unemployment rates of between one and two per cent constitute full employment while in the United States it can be between four and six per cent. There is no official definition in Hong Kong but unemployment of up to three per cent would enable economists to say there was full employment. Underemployment is the term used to describe those who involuntary work for 35 hours or less a week. Jim Wong, the Hongkong Bank's economic adviser, said: 'The labour market should remain quite tight. Unemployment should hover around the current levels because of the underlying economic growth.' Hong Kong's productivity growth is about three to four per cent a year while the labour force is expanding by between one and two per cent.