Fifty-five U.S. venture capital funds raised $8.1 billion in the third quarter of 2008, according to Thomson Reuters and the National Venture Capital Association on Monday.

That is 23 fewer funds and 6 percent less than the same period in 2007, reflecting a larger trend of fewer firms raising larger funds, association president Mark Heesen said in a statement.

But the $8.1 billion raised is still almost 60 percent more than the $5 billion committed to sixty-eight venture funds in the third quarter of 2006.

Mr. Heesen said firms with proven track records will be raising funds in excess of $500 million to invest in longer-term, capital intensive industries like life sciences and clean technology.

The ration of follow-on injections to new funds was close to 5-to-1 in the third quarter of 2008, compared with 4-to-1 in the third quarter last year.

The three largest funds raised in the third quarter were Sequoia Capital U.S. Growth Fund IV (later stage, $929.5 million), Austin Ventures X (balanced stage, $900 million), and InterWest Partners X (early stage, $650 million).