This week's official purchasing managers' index (PMI) for China missed some important components without any explanations, leaving strategists slightly puzzled as they try to assess what's going on in the world's second biggest economy.
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The data on activity in the manufacturing sector for June was released on Monday without a breakdown of results for at least four of the 12 sub components. They were new orders, backlogs of orders, quantity of purchases made by firms and imports.
"I don't think there's anything nefarious about this, but I don't know why they didn't have all the data, it was a bit odd," said Alistair Chan, a China economist with Moody's Analytics in Sydney. "Hopefully we will get those other details of the PMI report at some point."
PMI numbers were released across the world on Monday and are usually looked at closely for the latest update on manufacturing activity.
In China, economic data have proved particularly market-moving not just because of the size of the economy, but also as investors try to assess the extent of a slowdown that could have ramifications elsewhere.