BEIJING, May 10 -- China's producer price index (PPI), which measures costs for goods at the factory gate, went down 2.7 percent year on year in April, the National Bureau of Statistics (NBS) said Saturday.

In April, the purchasing price of industrial products dropped by 2.7 percent year on year, the NBS data showed.

NBS statistician Dong Lijuan attributed the decline primarily to imported international factors and seasonal decrease in prices of certain energy products.

On a monthly basis, the PPI edged down 0.4 percent in April, according to the NBS data.

For the January-April period, the PPI fell by an average of 2.4 percent compared with the same period last year.