Exchange-traded funds attracted $5.6 billion in assets in the third quarter, down considerably from the $12 billion attracted in the second quarter, according to Strategic Insight. ETFs brought in $23.2 billion through the third quarter, up from $15 billion in flows for all of 1999. Of the four competitors in the ETF business, the Bank of New York which manages the Nasdaq 100 ETF made the largest strides in the quarter, increasing its market share from 23% at the end of the second quarter to 29% at the end of the third quarter. With 50% of ETF assets, State Street Global Advisors still has the largest market share, but the percentage shrunk from 65% after the second quarter to 50% after the third quarter. Merrill Lynch and Barclays Global Investors, which own 11% and 10% of the ETF market, respectively, are up from 6% each after the second quarter.