If BDI rises significantly, it shows that countries' economies are in good condition and international trade is booming; On the contrary, it means that the economic depression will come unexpectedly. In 2005, BDI rose from 2000 to the highest point in 2008 1 1793. Almost at the same time, the rapid development of China's economy led to the recovery of the global economy. Raw materials from all over the world are continuously transported to China, Australian minerals, Brazilian sugar, American soybeans, Malaysian rubber and Middle East oil, which have led to the rapid prosperity of global shipping. These raw materials are an important part of the commodity market, so BDI index, as the value of maritime prosperity, not only reflects the demand for raw materials in the global market, but also becomes an important leading reference index for strategic investors in the futures market. BDI release: BDI index is released by Baltic Shipping Exchange to measure the activities of the 20 busiest routes in the world. Baltic Air Exchange is the first and oldest shipping market in the world. 1744 was born in Baltic Coffee House, Virginia, USA. At present, it is a world-famous shipping exchange, located in London, England. 656 companies from 46 countries around the world are members of the Baltic Air Exchange. In order to meet the needs of customers, Baltic Airlines Exchange began to publish the daily freight rate index-BFI at 1985. From 65438 to 0999, the international Baltic Composite Freight Index (BDI) replaced BFI and became a barometer representing the trend of the international dry bulk transport market. In the Baltic Exchange, there is a group composed of eight member companies, which is responsible for calculating the Baltic freight index for that day.