Futures arbitrage has an arbitrage range, that is, if it exceeds this normal range, arbitrage opportunities will appear. For example, if the difference range found after long-term research is {-100~300}, then if the difference is outside this range, you can make an arbitrage order. For example, if you find that the current difference is -500, then you can expect a profit of 400 points and you can arbitrage. If you find that the current difference is 150, you cannot place an arbitrage order within the normal range.