BEIJING - China's consumer prices steadied in September amid a sustained recovery of domestic demand, official data showed Sunday.

The consumer price index (CPI), a main gauge of inflation, was up 0.4 percent year-on-year in September, lower from a 0.6-percent rise in August, the National Bureau of Statistics said.

On a monthly basis, the CPI remained unchanged compared to the previous month.

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Meanwhile, China's producer price index, which measures costs for goods at the factory gate, went down 2.8 percent year-on-year in September, the bureau said.

On a monthly basis, the PPI edged down 0.6 percent, narrowing from a 0.7-percent decrease a month earlier, the data showed.

NBS statistician Dong Lijuan attributed the monthly PPI performances to fluctuations in international commodity prices and insufficient effective demand in the domestic market.

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From January to September, the average PPI decreased 2 percent from a year ago.