The size of basis is inversely proportional to the change of market supply and demand, and the size of basis is directly proportional to the trading volume and liquidity of futures market. The basis size is closely related to futures. Basis not only affects the investment strategy of market participants, but also reflects the relationship between market supply and demand and the future price trend.

Basis is closely related to the relationship between supply and demand in futures market. If the market supply exceeds demand, the spot price will drop, the futures price will also drop, but the basis will also expand. On the other hand, if the market is in short supply, the spot price will rise and the futures price will also rise, but the basis will be reduced. Basis is also related to the trading volume and liquidity of the futures market. When the trading volume and liquidity of the futures market are low, the gap between the market participants' expectations of futures prices and the actual market prices will increase, leading to the expansion of the basis. When the trading volume and liquidity of the futures market are high, the gap between market participants' expectations of futures prices and the actual market prices will narrow, leading to a narrowing of the basis.