New Delhi, May 4 -- Business momentum in India's manufacturing sector has marginally bounced back amid soaring crude oil prices and supply chain disruptions. The seasonally adjusted HSBC India Manufacturing Purchasing Managers' Index (PMI) rose from a four-year low of 53.9 in March to 54.7 in April. Despite the uptick, the April headline index data signalled the second-slowest improvement in overall operating conditions in close to four years.

The two largest sub-components of the PMI, new orders and output, rose since March, but were lower than the readings seen in at least three-and-a-half years. A factor that can explain April's manufacturing uptick is that consumers may have purchased before retail prices were raised significantly. S...