(IDEX Online) - Exports of Swiss watches grew again during September, driven by a huge 24 per cent increase in Hong Kong, the world's third biggest market.But sales in the US, representing about a sixth of demand globally, slipped by 6.4 per cent to CHF 344.7m ($381m) following a 13.5 per cent rise in August, according to the Federation of the Swiss Watch Industry Exports (FHS).China showed signs of recovery after sales fell by 27.3 per cent in August. In September that figure had slowed to 5.5 per cent.Overall Swiss watch exports globally for September were up 3.8 per cent year-on-year to CHF 2.3bn ($2.55bn) francs, slightly down on a 4.0 per cent increase in August."This change confirms the expected return to a normal level of growth," said the FHS.Most of the sales growth was among watches with an export price under CHF 200 ($221) or over CHF 3,000 ($3,320).Mid-market models (CHF 500-3,000 / $553-$3,320) declined by over 10 per cent for the third consecutive month.