First of all, shorting stock index futures is good news for investors in banks, securities and insurance stocks. These stocks usually perform well in bull markets, but often fall in bear markets. Shorting stock index futures can make investors profit from a bear market. Therefore, when the stock market falls, these stocks will become the biggest winners.

Secondly, shorting stock index futures is also good news for investors in technology stocks and internet stocks. These stocks are usually stable in a bear market because they can benefit from online business. If the market goes down further, these stocks are likely to go against the trend and become a "safe haven" for investors. Therefore, shorting stock index futures can not only gain the benefits of stock market decline, but also maintain the stability of portfolio.

Finally, shorting stock index futures is good news for fund managers who invest in the falling market. They usually support the stock market falling strategy. By shorting stock index futures, these managers can take advantage of the market decline to get a lot of income. This strategy is even considered as a protection strategy, which can protect their investment portfolio from market fluctuations.

Generally speaking, shorting stock index futures is good for investors who are bearish on stocks, fund managers with income strategies and the balance of portfolios. In other words, shorting stock index futures for some industries can achieve risk diversification and profit optimization of investment.