Over the past 12 months, there has been $4.4bn (£2.7bn) worth of deals, compared to $17.9bn during 2011.
In numerical terms, there have been seven IPOs in London in 2012, compared to 14 over the previous year.
The lower total IPO value this year reflected the dearth of blockbuster listings such as that of commodities trading giant Glencore in London in May 2011, which raised $10bn.
In sharp contrast, the US clocked up $47bn worth of deals this year on the NYSE and the Nasdaq, up slightly on last year’s tally, which came in at $41.1bn. The number of deals was broadly flat year on year.
The numbers were boosted by the mega-listing of social networking site Facebook on the Nasdaq in May, which at $16bn was one of the biggest floats in US history.
Globally, total offerings fell sharply with total IPO deal values across the top 10 exchanges coming in at $120.6bn, down from $168.5bn over 2011, according to Dealogic.
Last week, Kazakh mobile telecoms operator Kcell listed in London, raising $525m for its parent company TeliaSonera. Insurer Direct Line and Alisher Usmanov’s Megafon have also tapped the London market for funding this year.