The so-called continuous contract is to simply put together the main contracts at that time, so you can see that the price chart is actually discontinuous.

If you want to get a long-term sustainable trend, you must do something about it. General futures software should be available, such as Wenhua, which has a Wenhua index, such as rubber index and rebar index, that is, all contracts at the time of trading are weighted and averaged according to positions as weights, which is continuous in history. This is still very valuable.