Illiteracy rates are based on the percentages of people age 15 or above (classed as adults in most countries) who are not able to write and read, with understanding, a brief, simple statement about everyday life written in their home--or official--language. As might be expected, illiteracy rates tend to be higher in the lesser-developed states, where educational systems are a low government priority. Rates of literacy or illiteracy also tend to be gender-differentiated, with women in many countries experiencing educational neglect or discrimination that makes it more likely they will be illiterate. In many developing countries, between five and ten times as many women will be illiterate as men, and the illiteracy rate for women may even exceed 90%. Both male and female illiteracy severely compromises economic development.