New stock was issued at a breakneck pace in the first half of 2006, as companies tapped global markets both to expand operations and take over their peers. But the picture might not be as robust as the year progresses.In the first half of 2006, the amount of stock sold in initial public offerings rose 56%, compared with the same period last year, to $102 billion, according to preliminary data from Dealogic. Total equity issuance, which includes stock used to fund takeovers and sold by companies that already were public, rose 46% to $360.6 billion. In the U.S., the volume of stock issued rose 67%. The rate of growth in Asia was higher than in both Europe and the U.S. For example, equity issuance in South Korea rose 161% in the first half of the year, the biggest jump of any country. Japanese companies issued equity at twice the pace of last year. In IPOs, Italy and France topped the list, with deals in France up 193%, while deals in Italy rose 144%. The dollar value of all mergers and acquisitions rose 48% in the first half of the year to $1.8 trillion, according to preliminary data from Thomson Financial, compared with the same period last year. After much buzz about the expanding role of boutique investment banks in providing mergers advice, none ranked among the top 10 advisers for the first half of the year. Goldman Sachs ( GS) remained in the top spot, advising 206 mergers and acquisitions worldwide worth over $655 billion. Citigroup ( C) trails Goldman, with 176 deals worth $532 billion, and JPMorgan Chase ( JPM) is third, with 209 mergers worth $486 billion. Among the boutiques, Lazard ( LAZ) is ranked 11th and Rothschild 12th. Meanwhile, many of the deals in the second quarter came in the last two weeks. The financing of those deals will start early in the third quarter, when the environment in stock and bond markets is anything but certain.