San Francisco--Citing dramatically lower client trading and the economic downturn, Charles Schwab & Co. plans to fire up to 2,400 employees, or 11% of its work force. The cuts come after Schwab, the nation's largest financial firm serving financial advisers, cut 3,400 jobs, or 13% of its work force, in March. Both rounds of layoffs, combined with attrition, will leave Schwab's work force 25% smaller than it was at the beginning of the year. For the company-whose dramatic growth exemplified the online trading boom, leading its market capitalization to briefly surpass Merrill Lynch & Co.'s last year-the current marketplace is a dramatic reversal of fortune. It is unclear which Schwab departments will be most affected by the layoffs, and the company did not return calls by press time. In a statement, President and Co-CEO David Pottruck said Schwab remains dedicated to expanding the trading and administrative support services available to financial advisers. In January 2000, Schwab made its biggest move toward catering to the lucrative adviser marketplace by acquiring private banking kingpin U.S. Trust Corp. for $2.7 billion in cash and stock.