My country says inflation only 4% something like that but it's 20 or 25% some food 50%. I wonder if they had to use Mathematics in their approved Economy University? How do they calculate this inflation?
It is not that they do not know how to do it, they are purposely trying to deceive people with their fake math to try to make it seem as if everything is OK and the inflation is completely under control when the fact is that it is not like that.
If you want to know the real inflation then begin to keep track of the price of several key products, there are some websites that already do this but they may not have the information regarding your country, and once you do this for long enough you will get a more clear idea of the real level of inflation, once you know this information it would not be odd for you to think about whether or not it is a good idea to keep holding most of your wealth in fiat and if you should do something about it.