Asian markets had a volatile start, with Tokyo’s Nikkei 225 index dropping nearly 5% while Chinese markets surged on new economic stimulus. Japanese shares fell after Shigeru Ishiba was chosen to succeed Prime Minister Fumio Kishida. Ishiba supports raising interest rates and possibly corporate taxes, seen as less market-friendly than his rival. The Nikkei was down 4.7% by midday Monday. The yen strengthened, impacting exporters like Toyota, which fell 3.5%.