IPass, the US computer networking company, has become the latest initial public offering in the US to surge above its issue price on its first day of trading.

A recent report from Renaissance Capital, the independent IPO research firm, found that US initial public offerings rose an average of 25% above their issue price in the 12 months to the end of May. The nine companies that went public between December and May gained an average of 49% from their issue price, well outpacing the stock market during the period.