BEIJING - China's producer prices slid 4.6 percent year on year in March, the 37th consecutive month of declines, adding to disinflationary pressure, official data showed on Friday.

The drop in the producer price index (PPI), a measure of costs for goods at the factory gate, narrowed from February's 4.8 percent decline, according to the National Bureau of Statistics (NBS).

The index started a downward trend in March 2012 and has yet to turn around. The 4.6 percent decline last month was its second largest drop.

On a monthly basis, the PPI contracted 0.1 percent in February, narrowing from a 0.7 percent decline in February.

Experts said the continuous plunge in factory gate prices has added to disinflationary pressure in the world's second largest economy and might presage more monetary easing policies in the coming months.