U.S. stock futures are falling with decreasing confidence in the banking and retail industries. Lehman Brothers, which has already lost three-quarters of its value in the past four days, fell another 14 percent in trading before the stock exchange opened. Merrill Lynch stock fell 6.8 percent, and American International Group Inc. shares fell 14 percent. In retail, Macy’s Inc. lost 3.6 percent. Chain store sales fell 0.3 percent in August, according to the federal commerce department, due to increasing job losses and foreclosures.