It proved to be one of the busiest days of the year so far on the Irish stock market yesterday, as a 4 per cent drop in the value of the Iseq took the edge off a successful initial public offering for Smurfit Kappa.

The packaging group listed at €16.50, slipped back temporarily, but climbed to a healthy €17.55 in conditional trading before officially closing at €17.39.

Smurfit Kappa's gains - or future losses - will not be measured in the overall Iseq values until next week, however, so the index slid unabated in sympathy with negative sentiment on global markets without the newcomer's help.

AIB and CRH were among the companies to go ex-dividend yesterday, which also contributed to a sell-off, and dealers once again reported evidence of people switching their holdings from AIB into Bank of Ireland.

All of the financials suffered badly yesterday, with AIB the worst hit, falling 6.2 per cent to €21.95. There were plenty of sellers in Irish Life & Permanent, which went down almost 5 per cent to €20.00. Among the banks, Anglo Irish Bank held up best, dropping a mere 2.71 per cent to €15.82.

CRH, which is exposed to the US housing market, fell 5.75 per cent, dropping beneath the €30 mark to close at €29.32.

With long odds triumphing at Cheltenham, it was a good day for the bookies, and Paddy Power slipped just 8 cents to €18.67.

Grafton was under pressure, dropping 67 cents to €11.20, a fall of 5.64 per cent. There was strong volume in Kingspan, which dropped 4.37 per cent to €18.60.

Ryanair fell by more than 4 per cent, shedding 24 cents to €5.83, with traders attributing the loss to news that the Government might ban surcharges on credit card payments.