The Nikkei share average ended down 1.85 percent on Tuesday, its biggest percentage fall in four weeks, as a stronger yen prompted selling of exporters like Honda Motor Co. Ltd. Sumitomo Mitsui Financial Group Inc. also dropped after announcing a share offering plan, weighing on the overall banking sector. But Toshiba Corp. rose on a newspaper report of robust earnings. The Nikkei finished down 1.85 percent, or 303.86 points, at 16,124.35, almost wiping out a 316-point gain made during a three-day rally last week. The fall was the biggest percentage drop since December 14, 2005. The broader TOPIX index fell 1.54 percent to 1,659.03.