Volatility Analysis of International Dry Bulk Shipping Market: Based on BDI Index and Its Sub-Indices

International dry bulk shipping market volatility directly affects shipping companies’ operations and investors’ strategies. Based on 465 trading days of daily data from BDI index and its sub-indices (BCI, BPI, BSI, BHSI) from January 2024 to October 2025, this paper comprehensively analyzes market volatility using descriptive statistics, correlation analysis, risk measurement, and dynamic correlation modeling. Results show: (1) Indices exhibit significant volatility, with BCI having the highest (CV = 30.1%) and BHSI the lowest (15.9%); (2) High positive correlations exist between ship-type indices with time-varying dynamics; (3) Markets exhibit volatility clustering and asymmetry; (4) BCI has the highest risk while BHSI has the lowest; (5) Markets show cyclical volatility. This study provides guidance for risk management, investment decisions, and market forecasting.