ponder

The usual definition of literacy is exactly that: the ability to read and write one's own language. I believe that that is what is measured in this World Population Review of countries' education systems. The global average quoted in this report is 72.9%, with several countries found to have literacy rates of below 50% e.g.: Chad, 27%; Burkina Faso, 31%; South Sudan 35%; Afghanistan, 37%; Central African Republic, 37%; Niger, 28%; Somalia, 41%; Guinea, 45%; and Benin, 47%. In 2021, Thailand was found to have a rate of 94% in this survey (and this is the figure quoted in their 2025 report). Of course, this is just one factor examined, but I consider it a very important one.