http://www.nytimes.com/2010/11/18/b...=me&adxnnlx=1290139243-zZ6pTVKpmIvf+8rggn9+4w The annual rate of I.P.O.âs peaked in 1996, when around 756 American-based companies went public, according to Dealogic. That figure fell to a low of 36 during the financial crisis in 2008. It picked up to about 50 in 2009 and, so far this year, it is running at about 100, excluding G.M. Several companies are set to go public Thursday, in the shadow of G.M, including Anacor Pharmaceuticals and the broker-dealer company LPL Investment Holdings. But while I.P.O.âs have come out of their deep freeze, they are still running below the level required to hold constant the number of public companies. And that, analysts say, has unsettling implications for American job growth. âI would worry about the number of start-ups declining as they are the engines of the future,â said Eric Olsen, a senior partner the Boston Consulting Group in Chicago. âSmaller companies tend to drive innovation more than big companies. I worry about the lack of new companies.â Granted, many businesses are thriving privately, away from public exchanges. They are financed by private equity or bank lending.