According to this analysis, before 2004, the oil futures price of Midland was between 35 and 45 dollars. Buffett accurately judged that there would be a big bull market in Midland crude oil futures, so he revalued China Oil with huge oil reserves. Wachovia oil futures rose to 147 yuan in 2008. It has more than tripled and the market value of PetroChina has also more than tripled. From more than 30 billion, it rose to more than 654.38+00 billion. If you don't understand, you can ask.

Further reading: How to buy insurance, which is good, and teach you how to avoid these "pits" of insurance.