Six futures varieties need four screens. Ordinary investors use a four-screen computer, each screen is divided into eight windows, and 32 varieties can be viewed at the same time, and the overall trend is clear at a glance. Although there are more than 40 active varieties, only about 30 are left after subtracting highly similar varieties. For example, you don't need to look at soybean meal and rapeseed meal at the same time. Just look at a soybean meal. There is no need to look at corn and corn starch at the same time. Just look at starch. Four screens and 32 varieties are enough.