Average trading volume on the Nasdaq index is up 17% through the first half of the year, its main index rose 2.2%, and its listings continue to expand, too, Nasdaq Stock Market Inc. said Tuesday.

The Nasdaq composite increased 2.2% for the six-month period. This was driven by a strong second quarter gain of 2.7% and increases in the Nasdaq Insurance (9.6%), Nasdaq Transportation (9.3%) and Nasdaq Industrial (6.9%) composite sub-indices. After a 2.3% decline in the first quarter, the Transportation index gained about 12% in the second quarter, making it the strongest sector in the quarter.

Nasdaq average daily share volume for the six-month period was 1.9 billion shares, an increase of 17% over last year. Total share volume for the same period was up 17% to 234.6 billion shares. Market capitalization increased 30% to US$3.1 trillion in comparison to the first six months of 2003.

The Nasdaq also says that it captured 70% of the 105 U.S. IPOs that took place during the first six months of 2004.

This compares to five IPO’s during the first six months of 2003 and 83 IPO’s across all markets in all of 2003. The leading sectors were technology, financials and healthcare.

The exchange also added 10 non-U.S. companies in the first six months of 2004 bringing the total to 340. Additions include Canadian firms Geac Computer and Hemosol Corp. Seven firms that were already listed on the NYSE also joined Nasdaq. The exchange began actively courting NYSE companies in January.