LONDON - Pay was frozen in more than nine out of 10 types of investment banking jobs in the City of London financial district over the past year, according to research published on Monday by financial services recruitment firm Astbury Marsden.

The research, which looked at 142 different investment banking functions, showed there was no increase in the average basic salary in 92 per cent of jobs in the year to end-March.

Average pay fell in 3.5 per cent of jobs, while 4.2 per cent saw an increase in average basic salary.

Astbury Marsden's Chief Operating Officer Mark Cameron said that, although institutions had not been formally implementing pay freezes, a surplus of quality candidates and concerns over the euro zone crisis had created that effect.

"The surplus of good quality bankers, quants and other technical experts chasing a limited number of job opportunities and dearth in banking revenues has resulted in flat pay,"Cameron said.

"This time last year bankers were benefiting from substantial increases in base salaries but the euro zone crisis blew up and changed all that," he said.

A separate survey earlier in May showed bonuses for London's financial workers will be almost halved this year, falling to their lowest level in over a decade.