Summarize and humanize this content to 2000 words in 6 paragraphs in EnglishJapanese stocks ended lower amid persisting concerns over U.S. tariffs and many companies started trading ex-dividend.Auto and financial stocks led the declines, with Toyota Motor dropping 4.5% and Honda Motor shedding 4.9%, while Nomura Holdings fell 4.7% and Japan Post Bank lost 4.5%.The Nikkei Stock Average fell 1.8% to 37120.33. Investors focused on U.S. trade and foreign policies. The 10-year Japanese government bond yield fell 4 bps to 1.545%.