SYDNEY (AFX) - The better than expected September retail sales data is expected to contribute to a strong September quarter GDP to be announced next month, economists said. Retail sales in September fell a seasonally adjusted 0.1 pct from August to 13.636 bln aud, but were up 6.5 pct year-on-year, the Australian Bureau of Statistics said. The median market expectation for September was for a month-on-month fall of 0.5 pct, with expectations ranging from a fall of 1.5 pct to a rise of 0.2 pct. BT Funds Management chief economist Chris Caton said the increase in trade turnover of 1.6 pct is equivalent to 0.4 percentage points in estimated GDP for the September quarter. "Most forecasts for GDP growth in the quarter are now clustered above 1 pct. The future is another country but, at present, the Australian economy continues to do quite well, at least in a relative sense," Caton said.