CPI is a measure that's calculated by using the price of a standardized basket of things. It's indicative of inflation overall, but every person's personal inflation rate is different because it's affected by the exact mix of goods and services they buy, which aren't going to be the same as the basket.
If your family are experiencing inflation higher than 20%, it's because you're consuming more of things which inflate faster than the basket.
If your family are experiencing inflation higher than 20%, it's because you're consuming more of things which inflate faster than the basket.