What is the usual relationship between a country's standard of living and literacy rate of that country

What is the usual relationship between a country’s standard of living and literacy rate of that country? Usually the relationship between a country's standard of living and literacy rate directly relate to one another. When a country has a high standard of living, the literacy rate is also high because the norms are set to a higher standard. In society, everything relates to one another and because of one thing comes another outcome and so on.