In collecting literacy data, many countries estimate the number of literate people based on self-reported data. Some use educational attainment data as a proxy, but measures of school attendance or grade completion may differ. Because definitions and data collection methods vary across countries, literacy estimates should be used with caution. United Nations Development Programme, Human Development Report 2010. It is also important to note that the Persian Gulf region has had an oil boom, enabling more schools and universities to be set up.
