Banking giant HSBC has ended its five-year sponsorship of a closely watched series of business activity surveys, financial research group Markit, which compiles the data, said Friday.

The HSBC Markit Emerging Markets monthly purchasing managers' indexes (PMI) are seen by economists as a key gauge of manufacturing activity in China and other developing countries.

The companies' China PMI in particular is scrutinised for clues to the health of the world's second biggest economy -- despite often contradicting the official gauge released by Beijing.

"HSBC's sponsorship of Markit's Emerging Market PMIs has been a successful relationship over the past five years," Teresa Chick, a spokeswoman for Markit, told AFP.

"The sponsorship arrangement is now coming to an end and we will announce replacement sponsors soon," she said.

It comes as HSBC carries out a radical cost-cutting overhaul, with the bank saying earlier this month it plans to cut its global workforce by up to 50,000 in an attempt to boost lacklustre growth.

The bank is also exiting Brazil and Turkey and considering relocating its headquarters back to Asia from London.