Vol. 18 is a term used in futures, indicating the active selling volume outside the market. Volume index reflects the main trend of market turnover in a certain period.

VOL in futures is the main trend of market turnover in a certain period of time, which plays an important auxiliary role in matching with the moving average of stock price when judging whether the stock price is in the initial rising period, the main rising period or the final rising period, and the future changing trend of stock price.