Quantity and price are the same, so they are balanced.

If the price of that variety is very low now and there is an upward trend, then buy it up, that is, buy it at a low price and sell it at a high price. And the price of that variety is at a high price, and if there is a downward trend, short it. He sold at a high price and closed his position at a low price.

Extended data:

Common functions of shorting include speculation, financing and hedging. Speculation refers to the expectation of future market decline, and then sell high and buy low to obtain the profit difference. Financing means shorting in the bond market and returning it in the future, which can be used as a way to borrow money. Hedging means that when the risk of assets in the hands of a trader is high, he can reduce his risk exposure by shorting risky assets.

Short selling is an investment term such as stock futures: for example, when you expect a stock to fall in the future, sell it when the current price is high, and then buy it when the stock price falls to a certain extent, so the difference is your profit. It is characterized by the trading behavior of selling first and then buying.

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