Bulgaria's industrial producer price index (PPI) fell by 5.3% year-on-year in May, after decreasing by 4.3% in the previous month, the National Statistical Institute (NSI) said on Tuesday. The fall in the PPI in May was driven by a 7.0% drop in prices in the manufacturing sector, NSI said in a statement. On a monthly comparison basis, producer prices fell by 1.0% in May. The industrial PPI on the domestic market decreased by 1.6% on the year and fell 0.6% on a monthly comparison basis. The industrial PPI on the non-domestic market decreased by 10.7% year-on-year and was 1.7% lower month-on-month.