The HSBC Emerging Markets Index, a monthly indicator derived from Purchasing Managers' Index surveys, inched up to 50.6 in May from 50.4 in April, indicating weak output growth across global emerging markets.
While the EMI stood at 50.6 in May, the developed world's PMI was at 55.4 during the month.
"While the former points to an ongoing languor that has plagued the emerging markets over the past year, the developed world has moved into a higher gear and is now enjoying it strongest growth for just over three years," Markit Chief Economist Chris Williamson said.
During May, the HSBC composite index for India, which maps both manufacturing and services, stood at 50.7, whereas for China it was 50.2, Brazil 49.8 and Russia 47.1.
An index measure of above 50 indicates expansion.
"Disappointing performances
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